


Pompilos

by Mur



Category: Free!
Genre: Biting, Blood Kink, Dom/sub Undertones, Falling In Love, Frottage, M/M, Marking, Mentions of Drowning, OCs aren't actually OCs, Romance, Slow Build, Transformation, mermaid au, merman au, sexual instincts
Language: English
Status: In-Progress
Published: 2014-09-19
Updated: 2014-12-30
Packaged: 2018-02-17 23:08:42
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 9
Words: 32,964
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2326475
Author URL: https://archiveofourown.org/users/Mur/pseuds/Mur
Summary: <blockquote class="userstuff">
              <p>Alternatively titled: Help! My Roommate is A Shark</p><p>Rin is a shark who came to Samezuka Academy to train. He can't help being overpowered by his instincts. Nitori is an energetic teen who has unwittingly fallen head over heels for the shark. He can't help that he's accident prone.</p>
            </blockquote>





	1. Chapter 1

There were just a few things Nitori Aiichirou found strange about his roommate.

The first thing he noticed was the strange hours he kept. Rin was an athlete, so it wasn't strange in the slightest that he would come and go late at night, or the early hours in the morning to go running, or be at the pool before anyone else to swim laps (though usually their captain, Seijuuro Mikoshiba was there first anyway). Sometimes Rin would sit in the bathroom for hours with the water running or the shower at full blast. Occasionally the freshman would knock on the door to check if there was anything wrong, if he needed anything, or if he felt ill. The reply would be a grunt, or a "yeah," or something of the sort, and he would back off until later.

Sometimes he would spend so long in the bathroom that Ai would go down the hall to the general restrooms to pee, or just knock to inform Rin when it was dinnertime, that he was leaving for dinner, that he was back, or that he was going to bed. Sometimes he would wake up late at night and find that Rin was laying in the bath, or had gone out (presumably for a run or some fresh air). He wanted to express his concern about the matter, but at the same time, Rin was dismissive every time the subject was broached; soon enough Ai gave up with asking questions and accepted it. He had no problems with adapting to his roommate's eccentric sleeping patterns, or lack thereof.

The second strange thing about Rin was his teeth.

Ai had never been one to judge someone by their looks, but Rin's looks were...well. Superior. To everything. He had never seen a boy so eerily beautiful, or so naturally vicious. Rin acted tough all the time, but he came off more as a slave to his emotions than anything else, crying at the drop of a hat over being ditched at practice, misplacing something he had borrowed from his sister, or someone teasing him for his accent and teeth.

To be honest, they weren't normal teeth in the slightest. Rin would grin or cry, or just have this predatory _smirk_  before a race where Ai could see the faintest glimpse of his teeth, strangely razor-sharp, perfectly straight, perfectly white. They reminded Ai of the sort of thing he'd imagine on a monster from a comic book, or a shark. It wasn't in a bad way, either. They were weird, they were alluring. They were enough to cut the bottom of his lip if he bit down on them too hard. He tried not to watch Rin too intently when he ate, or how Rin licked his lips while deep in thought.

"Ai."

Sometimes he'd find himself thinking about what it would be like to have Rin's mouth against his neck, his teeth just barely grazing his skin, before he bit down, sinking them in--

"Hey, Ai."

\--pressing against him, wet and sharp, saliva and tooth raking against soft skin, drawing bl--

"Aiichirou!"

He sat bolt upright suddenly, roused from thought, and the odd staring contest he was having with the half-filled worksheet on his desk. "Huh? D-did you need something, senpai?"

Rin dropped his duffle bag on his chair, unzipping his track jacket. "I've been trying to get your attention for two minutes. Just letting you know I'm returning your English dictionary. It's on your bed."

He was regarding Ai with _that_ look again. It was so sharp, almost predatory. Sometimes Ai felt like those eyes were looking into him, past him, and right through to the wall. Even when Rin was upset or tired, they never seemed to lose their intensity. It was as though his eyes betrayed everything about him, and so little at the same time. They carried all of his emotions, but at the same time, they never really seemed _calm._

"Oh! Yeah, thanks, senpai. And also!" Ai leaned back in his chair, smiling over at Rin as best he could, glad that his face hadn't betrayed his thoughts to Rin. "Thanks for staying after practice with me the other day. I really appreciated it. If I work hard, I'm sure I'll get the hang of backstroke just like you taught me."

The taller boy exhaled sharply, shaking his head a little. He waved his hand a little after he tossed his jacket on top of his bag. "It's no big deal. Don't worry about it. Your technique is fine. You just need to practice until it becomes muscle memory."

Before Ai could get out a response, his elder had already stripped halfway down, and grabbed his towel.

"I'm taking a bath. I'll be out in about an hour."

That was the third strange thing about Rin. He was infatuated with the water. The way he swam at practice, before practice, after practice, on the weekend, and just about anytime, he just seemed to meld with the water. He cut through it with his hands, and propelled himself forward, towards some imaginary goal, towards some nonexistant finish line. He would drink five, six, seven bottles of water per day, and then spend hours in the bath at night. It didn't particularly bother Ai, but he did have to plan his day around it sometimes. He appreciated Rin for what he was, even if it was difficult to plan his day around. That said, most of his appreciating was of Rin's personality, skills, and appearance rather than his habits.

If only he could be like Rin too someday.

\--

At first, Rin was disappointed with the roommate he had been assigned. When he first came to Samezuka academy, he looked forward to training and classes, but he hadn't really considered that they'd pair him up with just about anyone for living quarters. After all, it was a school for the intelligent and the athletic, and he was surprised by just how familiar many of his fellow students were.

It wasn't altogether uncommon in underwater society to spend a few years of one's life on land covertly, but many whales, dolphins, fish, octopi, and sharks came to the shore to find wealth or a mate, after which they would steal away back to the ocean. There were plenty of fish in the sea, but even more on land.

Not that he was here to find a mate or wealth, but the thought of either of those things never bothered him.

His disappointment was rooted in the fact that the roommate he was assigned was just so...energetic? That wasn't the word for it. He was sure he could find a word for it, perhaps at three in the morning, when he was half asleep, when it was no longer relevant. He was cute, at least. Bubbly and mostly optimistic, a hard worker in both his swimming and his studies, he could give him that, too. He wasn't a particularly strong swimmer--the kid had technique and endurance, but he wasn't particularly fast.

After their first practice together, not only was Ai delighted that Rin was such a natural swimmer, but he very nearly idolized him. He outright declared that he wanted to be a swimmer "just like Rin" someday, and it became nothing short of grossly annoying. He liked having his ego stroked, he liked being told he was a fantastic swimer (ha, if Ai thought he was fast, he should see some of the underwater races Rin had), but something about the constant, excited greetings of "Senpai! Senpai! Senpai!" had the tendency to grate on his nerves. But that--none of that--was the real reason at the root of the problem.

"Hey, senpai! Do you have any more of those waterproof band-aids?" The warm, metallic-salty scent of blood tickled Rin's nose, and roused his senses. It was slight, so it had to be a tiny wound. A cut or a scrape or something.

Rin sank lower in the tub, as if pushing more of his body into the water would suck him down the drain, out into the ocean, and down into the bottom of the Mariana Trench. Why, oh why, did his roommate have to be so _fucking accident prone_  of all things?

He considered himself a respectable shark, much less a man-eater, not some overzealous pup who jumped at the slightest scent or sight of blood, but Ai's blood always smelled so mouthwateringly saccharine, it should have been illegal. _Yeah, sure._  He thought. _Sir, you're under arrest because your blood smells like something I'd want to pour all over my cheesecake like some kind of bizarre morbid serial killer dessert._  That'd go over fantastically.

Worst of all, the kid was succeptible to seemingly every injury known to man or sea. Bruises, cuts, scrapes, scratches, burns, bumps, anything. Even _worse_ , he never seemed to complain, whine, or even cry. If anything, he'd smile through the wound, say it was nothing, and go about cleaning it up. Couldn't he at least show /some/ kind of indication that his injuries actually bothered him?

"Uh, yeah," he replied noncommittally. "Look behind the mirror in here. There should be a whole box."

The door eased open slightly, and the smaller boy leaned in, sucking idly on his index finger. He smiled softly, removing the offending digit from his mouth to run it under the tap. "Thanks. It's uh, just a paper cut, but I know it'll sting if I leave it uncovered for practice."

The smell of blood was slight enough, but it was still enough for Rin to turn his head away. He tried (--and failed) not to imagine taking that finger away from those soft lips, and encasing it with his own, pressing his teeth against the edge of the wound to increase blood flow, drawing it in to kiss his hand softly and--

_Fuck._

And, of course, Ai seemed to notice. "Oh, sorry! Grossed out by blood, huh?"

He shrugged. "Yeah, kinda." The exact opposite of the truth, but to an outsider it made total sense, right? Yeah, sure.

Bandage acquired, his roommate was gone soon enough again, and Rin was left alone with his thoughts. The remainder of the night progressed just as any would, and his silver-haired roommate never mentioned the injury, or any others for the rest of the night. Rin wasn't sure why he couldn't stop thinking about that smell. The scent, the very thought of the blood was enough to send his mind into seemingly ridiculous fantasy that his waking mind had to scold him into suppressing.

\--

The next morning, Rin was up and out the door before the sun rose, leaving his younger companion asleep when he went for a run by himself. Strangely enough, Rin enjoyed running. It was nothing compared to swimming, but since he came to live on the land, nothing invigorated him quite so much, while simultaneously giving him plenty of time to think.

He'd been restless quite a lot as of late, a habit which he attributed to not enough exercise. It was easy for him to swim maybe five, ten, or even twenty miles a day in the open ocean. (Sharks who weren't distance swimmers typically only swam three miles a day, but Rin prided himself on speed and power.) In that tiny pool, he was maybe getting five miles a day maximum. It was like being caught in a too-small tank. It was probably find for most sharks, but a long-distance swimer such as himself needed exercise. He needed a _hunt_. He needed a _chase_. He wanted to be pushed to his limits and beyond, until his fins were sore, til his gills were nearly ragged. Swimming in human form was akin to swimming with weights; legs lacked the surface area and kicking power of a tailfin, which made him rely on his arms and build arm strength, dexterity, and speed. Only being able to breathe through his nose and mouth meant rationing out his breath and finding the right angles at which to breathe without losing speed. It was like the ultimate workout.

He slowed to a walk, finishing off the last of his waterbottle. He knew he couldn't continue like this without changing something, but he wasn't sure what. Maybe it was time to give Sousuke a call.

\--

"It sounds like you need a swimming companion."

Ok, not this 'you need to find a mate' speech again. "I don't know how many times I have to remind you that I don't need a mate," Rin snapped back.

"I didn't say _mate_ , I said _companion_."

"I don't wanna hear it."

"Oh, come on, you said yourself that you need a challenge," Sousuke's voice on the other end was close to a purr.

"Just because that's how your sexually-charged weird grudge match with that orca is playing out, doesn't mean that I get off on competition, thank you very much," Rin hissed.

"I never said anything about the orca," came the reply. Could he sound any more smug? If punches could be delivered through phone, Rin would have punched the smug attitude right off of his face. "I could tell you how we're doing if you wanted, but that'd spoil the fun."

The redhead made a face at his phone "Whatever. Look, running five miles a day isn't cutting it, neither is spending three hours swimming, or two in the bath. I even soak my fins, but I still want to rip something apart. I'm so restless, that some human kid could get a nosebleed after seeing some panties, and I'll jump him and bite a giant hole in his arm."

The other end of the line was silent for a few seconds. "What about a manta? Or a pilot fish? As aggressive as you are, I'm sure you could tame one."

Rin huffed at Sousuke's backhanded compliment, more offended than he wanted to let on. "Do I really strike you as the sort to try and train fish?"

"Do you want to find yourself pumped full of tranquilizers and dumped in a tank because you couldn't handle your bloodlust and bit someone's foot off? Because I don't." Silence. "Right. I thought not. Now go find someone who knows how to sate your bloodlust, or get the fuck away from humans."

 

**Notes for the Chapter:**

> Several years ago, I went to a little first-year convention called Shadocon. At this con they had a dance-off-type stage show, which was themed after Gurren Lagann. The whole plot was centered around how Simon was scared to dance and how Kamina was encouraging him and fighting all of the dance battles, until the main villain showed up and stabbed Kamina with a cleaver. Kamina had this sad moment on the stage and then died, and I don't remember much else about the show, but that was five years ago. I was laying awake writing the first draft of this chapter, and all I could think about was the fact that she stabbed him. With a cleaver. 
> 
> WITH A CLEAVER. A cleaver is a square knife, how does that even work. That is like seriously the least stabby of all knives, I mean I guess it makes sense because it's still sharp but. She stabbed him with a CLEAVER. That's what keeps me up at night.
> 
> Anyway, thanks for reading. This fic will probably round out to around ten chapters, and I have a lot of ideas for this universe, so there may or may not be a tie-in.


	2. Chapter 2

Ai sat on the edge of the pool, his feet dangling into the water. Practice had long since ended for the day, but he didn't want to go back yet. Rin was still swimming laps in the far lane but he wasn't entirely paying attention. He watched the ripples his feet caused, how even the smallest movement sent waves rolling across the surface. Everyone was training for the next competition; a series of timed events and a relay. He hadn't signed up for any of the events, just a segment of the relay, but he knew he'd have to beat out at least four of his teammates for the relay spot.

He lay back on the tile, staring up at the ceiling above as he listened to Rin's rhythmic splashes, trying to visualize himself in the race. Jumping off of the starting block, bursting forward through the water, pacing himself, putting on a burst of speed as he approached the wall. He would roll forward, pushing off with his hardest kick, surging back in the direction from whence he came. Water would speed by, pushing against his face and hands as he propelled his entire body forward.

He imagined Rin cheering for him, or an imaginary Rin swimming beside him, reaching for him, grabbing him. Rin's arms would wrap around him, lips on his neck, teeth piercing his skin as the surface closed overhead. Strong arms would enclose him, dragging him under. He'd open his mouth to breathe, bubbles escaping in a burst, but he'd only draw in water. His lungs would scream for air as he--

 _Ugh, not again._  His thoughts had completely derailed. The brain train had completely missed the station and somehow crashed and burned somewhere between romantic fantasy and absolute worst case scenario.

In the other lane, Rin finally emerged from the pool. "Ai, are you done for the day?"

He glanced up, grateful for the distraction from his thoughts. He was sure his face was completely flushed with embarrassment. "Uh! Not really! I was just visualizing. I'm going to swim a few more laps..."

"Hm? Training for competition?"

"Well yeah! Er, no! Kind of! I only signed up for one event. I decided I want to try for a spot in the relay, but I doubt I'll make it." He forced a smile, mostly so he wouldn't worry his senpai with how discouraged he actually felt. Visualization sure wasn't helping, either.

Rin wanted to shrug, not really wanting to bother to finish the conversation, but the forced smile was practically tugging at him not to leave. Why the hell was Ai so unintentionally cute? He couldn't bear to see him making that face. Not only that, but he actually did want him to succeed. The kid didn't realize what a disadvantage he was at. After all, Samezuka was a school for athletes and the elite. It was practically a given that over half of the swim team consisted of fish. "Well, I guess I could coach you a little, if you've got the time and energy left."

All of Ai, not just his eyes, seemed to light up at the idea. "Really? Y-yes! Please, Senpai! I mean, if it's not too much trouble!"

It wasn't until late that night that the two of them finally showered and went back to their room. Ai was so exhausted that he could barely walk, but it didn't stop him from smiling in the least. Instead of leaning against Rin's shoulder, he practically skipped ahead down the hall, grabbing Rin's hand playfully.

"Senpai, thank you so much for taking all of that time to help me! I really appreciate it! If there's anything at all I can do to repay you, please let me know!"

Rin merely grunted lightly in response, shaking his head. He wasn't sure how to tell his kouhai that he had been on edge as well, and the additional exercise had helped balance out his own restlessness. His overzealousness had evened out at least a little, and he felt oddly complacent and calm. How was he supposed to tell him that? _Yeah, actually, I needed that? I'm a shark and the very smell of your blood has me freakishly hyper-aggressive and I can't control my emotions or actions?_  Yeah, that'd go over swimmingly. "It's nothing, really. Don't mention it. Ever."

They walked in silence the rest of the way back to their room, and the only sound besides their footsteps was Ai's satisfied humming.

\--

Rin had expected that to be the end of it, so he was startled to find none other than Ai waiting for him after he finished his classes the following day. He was practically bouncing up and down with excitement. "Hey! Senpai! I feel like I really need to pay you back for the extra swim training you always give me, so, please let me?"

Rin slung his bag over his shoulder, rolling his eyes. It just figured that he wouldn't let it drop. Ai just wasn't that kind of person. "Fine, fine. What is it?"

Ai was grinning as he produced a flyer from his bag; one of those little tear-off ones Rin was used to seeing tacked onto bulletin boards. "Senpai, please allow me to treat you to the aquarium!" He finished with a bow, practically pleading. "I'll buy your ticket and ice cream and everything!"

He resisted the urge to laugh or roll his eyes. It sounded like one of the cheesiest things ever. An aquarium? He probably had already seen anything a place like that had to show him, but there were plenty of worse places he could drag him to. It was probably the sort of place that might make him homesick, but getting off of campus for awhile might alleviate some of his tension, as well. Being this on edge was driving him up the wall. He was so wound up lately that he was caught between punching a wall and crying, or crying because he punched a wall, and neither presented itself as a positive conclusion. He tried not to grumble, allowing a small sigh. "Fine. Let me go change out of my uniform and you can lead the way."

\--

Rin was grateful that the sky was overcast as they walked to the bus stop. The air was thick and humid, making the walk nothing short of miserable. Once they were finally on the bus, he laid his head back, letting the fan blow on his face. His legs felt heavy, so much so that he wanted to just lay there until they arrived. Sweat was trickling down his back, making his shirt stick to his skin. He briefly wondered why, as a being who came from an aquatic quiet, why being soaked with his own sweat was making him feel so absolutely dismal. It was ironic.

Ai, on the other hand, was all smiles. He kept his hands tucked into his jacket, his legs bouncing with extra energy. "Thank you for coming with me, senpai! To be honest, I've always wanted to check this aquarium out, but I was kind of embarrassed to go by myself." It was a little awkward to say, but he was genuinely glad to be out spending time with Rin, even if he had to admit that in the end his real motivations had been selfish.

The shark tried to feign indifference, shrugging without bothering to open his eyes. "So you dragged me along because you just didn't want to go see a bunch of fish in containers by yourself?"

Ai looked down at his knees, his smile fading "Well, yeah, kind of. I know I said I wanted to treat you, but yeah, I guess I was being a little self-centered." He paused, chewing on his lip. "But I thought you might enjoy it too! Fish always inspire me, I think they're pretty..." he trailed off.

Rin opened one eye, glancing over at him. What a pain. "No, it's fine. I appreciate it."

"Thanks, senpai. I'm sorry."

"Whatever. Don't beat yourself up about it, just enjoy the trip."

Ai sat up a bit more in his seat. "Y-yes, senpai!"

They sat in uncomfortable silence until the bus reached their stop, beginning the six block walk to the aquarium. Ai kept fiddling with his phone, trying to find the shortest route, but the directions weren't quite clear, and he couldn't get a good signal. Rin couldn't help but find his concern cute. Nitori was always so diligent about everything, which was admirable, but he seemed to lack the confidence to assert that he was good at things. Rin almost wished that it was socially acceptable to plant a kiss on his cheek and reassure him that he was doing fine.

Er, probably not. That was probably a bad idea, actually.

 _You smell so sweet, and all I want to do is hold you until that smile is a little more genuine and protect you from the world that's so determined to beat you up. Literally._  No, that wouldn't work in the slightest. It'd be better to start with baby steps.

"So..." he began, shifting his weight idly. "What made you choose to come to Samezuka?"

Ai was caught off guard at the question, watching the ground beneath him as he walked. "Well, I. I really want to be a swimmer. In middle school, I was sure I wanted to be a marine researcher, mostly of stuff like currents and tides, but my grades weren't spectacular. They were decent, but I wasn't near the top of my class. I got here though...and I saw he pool, and the swim team practice, and it was, well um. Something just clicked! I knew I wanted to be a swimmer. Not an olympic or competitive swimmer, but I could be a diver, you know, for animal rescue or research teams or something! But--oh! I'm sorry. I'm rambling a lot."

"No, it's fine. So, you saw us practicing, and just that inspired you to start swimming?" He couldn't help but chuckle.

"Well, yeah actually! I couldn't take my eyes off of you! I think you're really beautiful, senpai!" He stopped, heat creeping up his cheeks as he realized what he had just said. "I mean! Your swimming is beautiful! I couldn't stop watching you! I meant! Um! Nevermind!" He bristled, then went silent again, and went back to fiddling with his phone.

"Have a little more confidence in your directions," Rin said abruptly.

"Er, thank you! I've just never been to this part of the city before..." he trailed off, glancing at his phone, then the street, and back at his phone.

"What's wrong now?"

"It should be right here..." Ai murmured, indicating the vacant lot next to them. "I'm sure I followed them the right way..." He looked back down at the directions, turning his phone around and around. "Maybe I had us take a wrong turn somewhere, but I was sure this was the right address!"

Rin didn't say anything for a few moments, but slowly reached forward and rubbed Ai's shoulder reassuringly.

They walked around the city in circles for what felt like hours, and in the midst of their wandering it began to rain. In the end, it was already dark by the time they found the real address of the aquarium, several streets down. Tired and soaking wet, Aiichirou seemed as defeated as ever to find that it was already closed for the night. He perked up a little when Rin promised him that they could try again the next time they had a day off from practice, but for now it was probably best to head back, dry off, maybe watch a movie, and go to bed.

Ai was satisfied with the offer, shaking off his dejection as best he could when they finally got back to the dorm. Once they returned to their room, they hung their wet jackets and shirts over the shower curtain, and left their pants and wet socks on the edge of the bathtub. They changed into dry pajamas, and wrapped up in their blankets, and curled up on their respective bunks. They both agreed that they were too tired to even bother with a movie, and went to bed early instead.

Curled up on his bunk, Rin was altogether surprised with himself that he didn't feel let down by the day's events. The walk was miserable, the rain had been unbearable, and they hadn't even succeeded at what they set out to do. He felt more like a beached guppy than a travelling shark, but his tired body be damned, he felt....oddly calm. Being with Ai seemed to soothe him somehow; all of his tension melted away in the freshman's presence. He just wished he didn't bleed so often. The kid could cut his hand open on a paring knife, a splinter, _something_ , and he wouldn't be able to control himself anymore.

What did that even _mean?_  That Aiichirou would cut himself on a paring knife, a paperclip, a _splinter_ , and he'd pounce him? Then again, the smell of his blood was practically intoxicating. He wanted to lick his wounds, tasting the fresh blood, bite into his skin, grab him by the neck, sinking his teeth in. He wouldn't take a bite, just bite to bite. Enough to draw some blood, leave a mark, and --wait, bite his _neck?_  Why was he thinking about mating, _at a time like this?_  And mating with a human, no less! He had no intention of staying on the land, nor did he care to drown the kid, so those thoughts were best if they were stomped out. If he actually wanted someone, maybe he should actually focus on what Sousuke told him, in spite of how much he didn't even want to bother, let alone admit that the whale shark was right in the first place.

Rin groaned, rubbing his eyes with the heel of his palm. What a pain. He rolled over, pulling the blankets over his head. This shit was something he'd have to deal with another day.

**Notes for the Chapter:**

> I know this chapter was a bit more serious, but bear with me, it's setting up for a LOT that's going to happen later. Also the next chapter will have the introduction of a few "OCs," but they're actually just characters that happen to cameo from other sports series. I promise you don't need to know anything about those series to understand everything that happens. They're literally only here to help push the plot along and aren't really super-important to the story at all.
> 
> Thanks so much for reading! Chapter 3 will be up soon!


	3. Chapter 3

Rin was still asleep when Aiichirou left for class the following morning. He made two attempts to wake him before leaving, but the shark groaned and waved him off both times.

He dropped by to check on him during lunch, but Rin was still asleep. He was huddled up in a wad of blankets, so he appeared to be more of a mass of lumps wrapped in fabric than a person. Ai smiled a little and shook his head, dumping the extra lunch he brought into his personal bento. It wasn't anything fancy, (he wished he had paid more attention to Rin's diet aside from protein bars) just some rice and tako-san sausages, and eggs on the side. Overall, it was probably bland, but on the off chance that his roommate was sick, he didn't want to take any chances. He took a sticky note from the desk, scrawled a quick message on it, and left it on the nightstand beside Rin's bed for whenever he woke up. _I brought you some lunch, feel free to dig in! I hope you're feeling better. - Ai_

After his classes were over for the day, Ai returned a second time. The bento was empty, and an empty water bottle sat beside it, so he assumed that Rin had at least woken up at some point. He crept over to Rin's dozing form and placed a hand against his cheek. Just as he feared: not only did Rin have a fever, but he was sweating horribly, too.

A wave of guilt surged up inside Ai's gut; there was no doubt this was from being caught in the rain for so long the previous night, then walking back from the bus stop in soaking wet clothes. _This is all my fault,_  he thought. _I'm incompetent at everything, and he always has to help me._  Even the things he did for Rin to say thank you ended with Rin helping him instead. They would have never made it back the previous night without Rin's navigational skills and ability to discern directions from tiny landmarks and road signs.

Ai sank to his knees beside Rin's bed with a sigh, replaced the empty bento with his dinner leftovers for Rin, and lay there for a few moments, watching Rin's breathing. He'd have to find another way to say thank you, and that he was sorry.

\--

Practice that evening was shorter than usual. Captain Mikoshiba walked everyone through warm-ups and a few quick practice races, then left everyone to practice on their own. Ai stretched out while waiting his turn for a lane, and sat with his feet in the shallow end. His mind was occupied with thoughts of Rin, rather than focusing on his strokes when their captain popped out of the water in front of him, spraying him as Ai nearly jumped out of his skin. Seijuuro was all smiles.

"Oi! Nitori! Why haven't you signed up for any of the events for the competition yet?"

"Oh, um, well, I was thinking I would just try for a spot in the relay. I'd rather do a relay, and I like team events," Aiichirou explained, chewing on his lower lip.

"You sure? Well, if you are, do your best and train hard! You still have to earn the spot, and I know a few of the second-years are gunning for that same spot too."

Ai nodded, perfectly aware of his own disadvantage. He was training hard to improve his times, but it was hard to train when he was so preoccupied.

"So what's up with Rin? Is there any reason he's not here right now? Big exam tomorrow?" His elder asked, and Nitori deflated with a small sigh.

"He's....sick with a bad fever. Hasn't left the bed all day. We got stuck in the rain last night, so--"

"Say no more!" the redhead took Ai's hands in his own with a dramatic flourish. "My dear Nitori, I'll be your personal swimming coach until your senpai's condition improves! We'll do one hundred laps front crawl, and one hundred laps backstroke! I will ensure that you don't lose even a single second of training!"

"M-Mikoshiba-senpai! Please, it's all right!" Ai was practically flailing in dismay at the offer. Their captain was serious--way too serious about swimming. He'd keep him there all night, and then some. He knew he meant every word of it. "I'm doing fine in my training, I promise! Besides, I don't want to take away from your personal training time!"

The captain paused, and Ai held his breath, hoping that he was genuinely considering it. If the captain trained him, he was certain he'd be dead within the day. Luckily, Seijuuro smiled, and Ai dared to let the relief play across his face "That's really considerate of ya. I have another idea, then. Oi! Nishinoya!" His boomed out across the pool, and the smallest second year Aiichirou had ever seen popped out of the water two lanes over with more of a splash than was in any way necessary. He had bright eyes, and dark messy hair with a blond tuft poking out of the front of his swim cap in the front. He recognized him from the short-distance group of speed swimmers on the team.

"Yes sir, captain, _SIR!"_

Ai winced. Damn, he was loud.

The captain smiled. "Nishinoya, you swim laps with Nitori here. Help him boost his speed, and he'll help you with endurance."

"You got it, captain!" He shouted with enthusiasm as Ai dipped himself to the pool, nodding his thanks to their captain, and swam over to the other lane.

"Thanks for swimming with me, Senpai," Ai murmured, stretching again quickly before pushing off of the wall.

"It's no problem!" He answered with a grin, and Ai briefly wondered how he could possibly talk while swimming. Not to mention he shot ahead quickly, so fast that Ai wondered if he even would be able to catch up. On the other hand it was easy enough to tell that his practice partner wasn't a long distance swimmer, as he slowed down early on their return lap, and Ai managed to pass him. They stopped together at the end, waiting until they both caught their breath. Next lap, he was already ahead of him again, but Nitori managed to catch up to him sooner, but not soon enough to stay ahead.

They went back and forth until practice was over, and Ai thanked him for agreeing to swim with him.

"Nah, it's all good! After all, you called me senpai!" his companion shot back with a wave.

Nitori spent longer than usual in the shower after practice, letting the water pound against his back. He couldn't get Rin off of his mind. He knew beating himself up about Rin's illness wouldn't do him any good, but he was still wracked with worry. Despite his worry, he couldn't stop his mind from spinning in circles like a centrifuge where he was caught along for the ride.

He imagined he was standing ankle deep in the ocean, the rain beating against him. Rin would emerge from the water, grabbing him by the wrists, digging into his skin with eerily sharp nails; dragging him forward, he would pull Ai's legs out from beneath him. He would fall forward crashing into the waves, but suddenly the depths would seem endless with Rin centimeters from his face, bright red eyes boring into his very soul. He scolded himself for likening them to untouchable rubies, buried somewhere deep beneath the ocean's surface. Rin would come closer, then lunge forward, kissing him passionately, teeth digging into his lip and scraping against his tongue, stinging as they drew blood. Ai, lurching back, would strain against his grip, but Rin was unyielding. Ai tried to breathe in, but all that could reach his nose or mouth was water.

"Aiichirou? Are you all right?"

He snapped back to reality, sitting on the shower floor. Seijuuro was standing in the doorway in a towel, concern etched all over his face.

"Oh! Yes! Sorry!" He hurried to turn off the water, grabbing for his towel. "I guess I zoned out a bit. I'll um, see you tomorrow, Captain!"

He dried off quickly, and changed back into his dry clothes. He balled up his swimsuit inside his towel, stuffing it in his duffel bag, when Seijuuro stopped him.

"Aiichirou Nitori." He put a hand on his shoulder.

He bristled at the sound of his full name. "Yes?"

"We're having qualifiers for who goes to competition on Friday. Win your heat, and you get to go. I want to see you go, but you're at a disadvantage: so train hard, okay?"

"Y-yes! Thank you!" He bowed as the captain picked up his belongings and walked past him, still wrapped only in a towel, to go lock up the pool.

\--

Laying in bed all day was absolute misery for Rin. He needed to be active! He needed to swim! Mostly, he needed to water. But instead, he could barely move, fever gripping his body.

His entire body felt dry, right down to his fingertips. Every hot breath he drew in felt worse, like he was choking on paper. The thin layer of sweat brought on by the fever had coated so much of his body that the presence of the salt on his skin made him feel scratchy and as though he could just peel his skin off in dry sheets. Salt water always felt nice, but dry salt on his skin seemed to have the opposite effect. Was he drying out? Maybe, but his limbs felt so heavy, and lethargy spread over him time and time again.

He willed himself to move, but his body refused to allow him to stay conscious for more than a few minutes. He couldn't even bring himself to sit up until sometime around 2PM, and even then it hurt to move. His limbs felt weak and heavy, and the process of getting up was painfully slow. He had to get up this time. He felt like he was drying out. He needed water. To drink, or to submerge himself in. Either would work.

_Come on, Rin Matsuoka! You are a PREDATOR of the SEA. If you dry out and die here, you're pathetic._

He slung his feet over the side of the bed and hauled himself into a standing position by holding onto the top bunk for support..

_Okay. Standing. This is a good start._ If he could even call it a start. He uncurled his fingers from the bunk, took two steps, and tumbled forward, catching himself on the desk chair. He almost knocked it over, lurching forward as his legs buckled, nearly fully giving out beneath him, and he clung to the chair for what felt like an eternity before dragging himself upright.

_If you let yourself dry out, you're an urchin. A mindless, spiny, invertebrate URCHIN._

He staggered a few more steps to the bathroom, feeling triumphant as he managed to make his way to the sink. He turned on the faucet, letting his hand sit under the running water for a few moments, before he sank to his knees, listening to the sound of the water running.

_...And if you did dry out and die, what would happen to Aiichirou?_

He wasn't sure how long he sat there. He couldn't stop thinking about Ai. Was he doing well at practice? Did he hurt himself again? Rin was willing to bet that he blamed himself for this fever, too. He soaked his hands and washed his face in the sink, feeling rejuvenated, (though still really sick) from the water. He filled the waterbottle he kept under the sink, downing the entirety of its contents twice, before filling it a third time and retreating back to his bed. It wasn't salt water, but it would have to do.

Once back in the bedroom proper, he noticed Ai's bento on the nightstand. Had he forgotten his lunch? Maybe not. There was a note tucked under the corner, carefully folded, which Rin assumed was for him. Upon reading it, he swallowed a sigh. _Shit, I've been really selfish,_  he thought. _He's been worrying about me so much. I'm being a pretty shitty senpai, huh?_ Maybe the kid was starting to grow on him. Just a little. Anyway, that was all he was going to allow, and he put it out of his mind as he scarfed down the rice and sausages.

\--

Rin was awake when Ai returned from practice, but made no move to show that he was conscious. He kept the blanket over his shoulders, watching him through half-lidded eyes. He gave into the temptation to watch him while he dumped his duffel bag onto the chair and changed into his pajamas. He watched him wiggle out of his workout pants, mildly surprised at how lean and toned his legs were. Ai always seemed so scrawny, but it was clear that he had worked hard to attain such a nice body, (considering that naturally, he was so small).

Legs were still a fairly new concept to Rin, but, being an athlete, he could appreciate well-developed muscles. Well, being an athlete was part of it, but most of it was due to his sister's fascination with them. Aiichirou's legs were desirable, but so was his shapely round buttocks, and slender back.

_Stop staring, you pervert. He's off-limits to you, anyway. He's making you hot. Maybe that's the fever._

He shifted a little, pulling the blanket over his head. He lay there in the dark under his covers, trying to imagine what Ai would be like if he came from the sea. With a body like that, he'd be an adorable manta. He tried to picture him with the wings on his arms and long tail. _(No. He's too small for that)_. Mantas were more about upper body power to propel themselves through the water, and Ai seemed more balanced than that. _What about a seal?_ He did have the puppy look down, but seals weren't quite as graceful as he was. _Maybe a lionfish?_ A fanned striped tail, stripes etched into his torso, long spines stretching along his vertebrate and down his back? Certainly an exotic specimen, but it didn't seem to quite fit Nitori. He decided that stripes /did/ suit him, though. _(I bet he'd look even cuter with stripes.) Wait, what? Fuck, Rin. Pull yourself together._

Luckily for Rin, his fever didn't allow him to stay awake for long, cutting his thoughts short before he could properly scold himself. Instead, he drifted off into an uneasy sleep, filled with dreams of the ocean and all its wonders. Or rather, the wonders it was lacking. The wonders he wished he could have in his arms, against his tail, held close to him. He needed to force himself to get over it, but somehow, he had decided (against his own better judgement) that he wanted him. Even if Ai was scrawny and confined to dry land, he'd belong to Rin. A land boyfriend. Yeah. All he had to do was court him and claim him without him realizing Rin's true form. What could possibly go wrong?

**Notes for the Chapter:**

> Now that Baja blast is basically sold out of every store ever, I don't know what to do with my life anymore. I mean, I can always sit here and write more stories about anime boys falling in love with one another, but I COULD be sitting here writing stories about anime boys falling in love while drinking baja blast. The latter option sounds so much more satisfying, but sadly I am lacking in delicious teal-coloured soda. 
> 
> Rin's finally warming up to Aiichirou, but things are about to get really messy.
> 
> Thanks a bunch for reading!


	4. Chapter 4

Friday came quicker than anyone expected. Rin was well enough to start attending practices again on Wednesday--not that he needed it. He won both of his heats effortlessly, and in nearly record time. Mikoshiba even went so far as to tease Rin about it, urging him to put more into it, he could break the school record next time. Rin waved him off, more peeved than interested in listening.

Ai was in the last heat. When it was time, he stepped up onto the starting block, and dove forward at the sound of the second whistle. He could hear Rin cheering for him, his cheers very nearly drowned out by those of a small second year sitting behind him on the bleachers.

He was off to a faster start than usual, but he couldn't quite manage to pull ahead. A tall second year who Ai was fairly unfamilar with--Kagami, he thought his name was--had ridiculous dives that hit the water nearly a meter and a half ahead of him, and he pushed himself as hard as he could to catch up. His pace slowed a bit towards the end of the lap, counting on his kickoffs to help him get his speed back up, but he miscalculated his distance from the wall, and couldn't get as much power from his kick as he wanted.

The swimmers to his sides passed him, and he tried to clear his mind. It was better to focus on his time than the other swimmers. He needed to focus on the goal. On the second half, he took fewer breaths, electing for deeper ones rather than fewer, more shallow ones to conserve energy for his final burst. When there were only ten meters left, he kicked harder, and put on an extra boost of speed, expending almost all of the energy he had left at once. He reached as far forward as he could with each stroke, until his fingers touched the wall. _There!_

He nearly threw his head out of the water as he touched the wall, lowering himself to a standing position in the shallows to catch his breath.

Third. He hadn't made it. _Oh._  Well, there was always next time, right?

What he didn't consider was that Rin would be broken up about it. Captain Mikoshiba beckoned everyone to the edge, with the clipboard of everyone's times in hand. He went down the list, reading off the names of everyone who would be in the competition, and what events they would be participating in.

Once he was done, everyone began to split off from the large group, but Rin stomped up to their captain, and slapped him in the face.

The everyone present fell into a stunned silence. Rin could be passionate and rude more often than not, but he never raised a hand to a teammate.

"The hell do you think you're doing?!" he demanded.

No one dared to interject. The captain appeared to be as calm as ever. "Reading off the roster," he answered flatly.

"Your roster is _bullshit!_ " Rin snapped.

"And what's wrong with it? I did it by times. Any of my personal biases aside, times dictate the roster."

"You mean to tell me that Aiichirou didn't make the cut?" Rin demanded, and Ai sunk down a little in his lane. They were standing in the shallow end, where the water was barely a meter deep, but he wished the pool beneath him would open up and swallow him whole. All of this was over him? Why? There was no reason for such an outburst. Had his loss really disappointed Rin _that_  much?

Seijuuro's eyes softened. "I'm sorry, Rin. The times are the times. I'm not going to make everyone re-compete."

"No! You're being a biased asshole, and you know why!"

"Then maybe you should tell _the team_  why."

Rin fell silent. He couldn't say it out loud in front of the entire team. The whole roster consisted of Marine life. Not a single human had made a short enough time to make the cut. It wasn't fucking _fair!_   Aiichirou had worked so hard, and was still able to take the time to take care for him when he was sick. He _deserved it!_

Ai climbed out of the pool, decisively placing himself between the two of them on the water's edge. "Stop! He's right, Senpai. I lost fair and square. It's okay. Let it go."

"You don't understand!" Rin shouted, and the smaller boy shrank back, but forced himself to hold his ground.

"What don't I understand?" he asserted, planting his hands on his hips.

"I can't tell you!"

It was then that Mikoshiba decided to interject once more, putting up a hand. "Rin, let's all calm down and--"

But Rin wasn't having any of it. He turned to swing at the captain, but Nitori moved to block him, grabbing his arm. As a jerk reflex, Rin moved to toss him off, in turn, shoving Aiichirou backwards into the pool.

His back hit the water first, and slammed against the concrete-and-tile bottom of the pool, followed by his head. He bit down on his tongue, _hard_ , and gasped from the pain, but in opening his mouth, ribbons of blood escaped into the water paired with bubbles, and water rushed in. The water around him grew murky and red, and he wondered briefly how hard he hit the bottom. _Where am I bleeding from? What's happening? Where's Rin?_

\--

Above the water's surface, Rin was stunned. He stood there in numb confusion as everything seemed to happen in slow motion around him. Aiichirou hit the water. Seijuuro roared with the voice of a tidal wave crashing the shore as he demanded everyone retreat to the locker room and designated a few specific people to stay and help Nitori. He then tore off his shirt and dove into the pool, wrapping one arm around the boy's waist, one hand cradling his neck to keep his head steady, and hauled him out of the water.

Rin blanched at the sight of the blood blossoming in the water. It was entirely his doing. He couldn't look at this. Even smelling it was overwhelming. He left, his eyes welling up with tears as he fled, shoving past a few dumbfounded teammates and out into the hallway.

\--

Aiichirou felt thick arms wrap around him, and he sputtered, coughing up mouthful after mouthful of chlorine water.

"He's got him! Clear the way!" Was that Nishinoya's voice? It seemed fainter than usual. He knew he was out of the water, but everything around him felt like he was still underwater, blurring and twisting as if he was looking through the wrong end of a kaleidoscope. His head and back throbbed with pain, and he could taste his own blood mixed with the pool water in his mouth. He couldn't move, either. His nose and chest were burning from inhaling so much water, and his vision clouded further, until it went dark.

The voices around him kept fading in and out, and he let his eyes droop closed, too tired and in too much pain to keep them open. There were so many of them, and they seemed to blur together, like he was hearing them from the end of a long hallway, rather than them being right beside him.

"He's unconscious! Someone get a towel over here!"

"Make a space! Give him some air!"

"I brought a towel!"

"Should we take him to the hospital?"

"There's no time! We're making it right now. I can't believe Rin, where the hell did he run off to?"

"Oh my god, did he cough up blood?"

"It doesn't look like it, I think he just bit his tongue."

"Oi, Sakamichi, get over here and hold his head for me, roll him onto his side. If there's more water in his throat, he's just going to choke on it if he's left laying on his back."

"Y-yes!"

"Everyone, calm down! I'll heal him." At least he could recognize Mikoshiba.

Ai felt the hands of the captain on his back, and the smaller hands of one of his teammates cupping his head as they rolled him onto his side. His chest burned, and he coughed, sputtering up the remainder of the pool water and his own blood he had swallowed. He felt something cool and soothing against his back, and again against his head a few moments later, and the pain in his shoulders and back subsided. There was a voice above him, Mikoshiba's voice. "Ai? Aiichirou, can you hear me?" He willed himself to move, his head, his arms, something. His head was still pulsing, and the best he could do was mumble out a pained groan. He felt wind against his face, from where, he wasn't sure. He assumed he was dreaming.

The pain in his mouth ebbed, replaced by a cool feeling he couldn't quite describe. He felt multiple hands grab him, a quick countdown, and he was lifted, probably onto someone's back. He could hear them all chattering at once, giving directions, cleaning up, but their voices still sounded muddled.

\--

He awoke to find himself laying in a bed, Rin's bed, by the smell and feel of it. He was still too exhausted to open his eyes, but at least everything sounded a little clearer now. He could hear Rin and Seijuuro's voices arguing.

"Look, you know I'm right! It doesn't matter if you don't want to accept it, but everyone who made our lineup is a seadweller!"

"And how else would you accept as a fair strategy? How else _should_  I choose?"

"I don't know!" Rin's voice sounded choked. "You know this isn't fucking fair!"

"You know other schools would see us as stacking our deck for taking a different route. The roster stays." Seijuuro's voice was firm.

" _I'm_  the top of the food chain! You have to listen to me!" Rin hissed.

"I am not obligated to listen to anyone, much less an overgrown pup. You're acting entitled. Get a grip, Rin!"

Ai heard a small sniff. Was Rin crying? "I'm...sorry I yelled at you earlier, and I pushed Ai in the pool. Fuck, he'll hate me for this..."

"No, he won't. I used my powers to heal his wounds, they weren't too severe. He somehow didn't even suffer a concussion. In a few hours, he'll wake up with some bruises and scrapes and he'll be none the wiser. But." His words hung heavily in the air. "You do need to apologize to him, and stop trying to fight his battles. Humans aren't like us. They're all the same kind of animal."

There was a creak, and Ai assumed one of them sat down on the desk chair, and he felt a weight at the foot of the bed a few moments later, which, by the shape of it, was probably Rin.

There was a long silence before anyone said anything, and he heard Rin sigh.

"But, are _you_  okay?" Seijuuro asked.

"To be honest, I don't know. All of this is my fault. I'm...going to need some time."

"Fine then." He didn't sound angry. Just as though he was deep in thought. "I'll settle things with the team, so you won't be in trouble or suspended from the relay, and clean the pool. We're removing any evidence of this and never speaking of it again. As for Aiichirou, the rest is up to you." There were footsteps, followed by the sound of the bedroom door opening and closing. After a few minutes, he felt the weight leaving the bed, and the water running in the bathroom.

\--

He wasn't sure how long he had been unconscious, but nothing made sense. What was Rin talking about with the captain? Healing powers? Seadwellers? What? Seijuuro even said that they weren't human. What were they, then? Aliens? No way. But he did say seadwellers, fish, and at the top of the food chain. Did that make them some kind of sea monsters?

Maybe he dreamt it. It had to be a dream. None of it made sense.

He stirred, realizing how dry his throat was as he tried to swallow. He grumbled, forcing himself to roll onto his side. He forced his eyelids open to see Rin emerge from the bathroom and rush to his side.

"Aiichirou! You're awake! Are you okay? Is there anything I can do?" He took Ai's hands in his own, a look of concern plastered across his face. He seemed like he was being unnecessarily overbearing, but it somehow also felt genuine. He couldn't quite place why, but he also didn't particularly mind.

"I uh..." he mumbled, propping himself on his elbow when something wet hit the back of his palm. He glanced downward to see a round red dot of liquid, suddenly accompanied by a second, and then a third. He reached up to touch his face numbly, the realization slowly dawning on him.

Oh _No. Nosebleed._  He half expected Rin to lurch away, since he was fairly certain he was squeamish.

Instead, Rin was transfixed. He stared at him, as if in a daze. No, not quite a daze. His gaze was more concentrated. It was _predatory_.  Ai wanted to shrink away, but at the same time, if this was a dream, here was his chance. He leaned forward, letting his forehead rest against Rin's, and let his lips brush against his, savoring the smell of Rin's breath, despite it mixing with the blood pooling on his upper lip. (It felt gross. He was trying not to think about it. If he just enjoyed the moment, maybe it'd vanish. That was how dreams worked, right?) He wrapped his arms around Rin's head, pulling him into a soft kiss. The other froze, but he cheered inwardly when Rin licked the blood off of his lip. Slowly, hesitantly, he began kissing him back.

Ai closed his eyes, nibbling on his lip, coercing Rin into parting his lips once more. When the other obliged, he slipped his tongue in, savoring Rin's taste and letting his tongue trace every aspect of Rin's mouth; his lips, his tongue, the edges of his teeth. Yes, this was what he wanted. He pressed his tongue against Rin's tooth, purposely cutting it, letting Rin taste him. If it turned out that Rin was some kind of sea monster determined to eat him alive, so be it.

Rin stiffened, realizing what he was doing, and pulled back with a start. He stared at Nitori for a few seconds in shock, his face dripping with his blood. He staggered back, then snatched a few tissues from the desk, wiping his face with one, and practically throwing the rest at Nitori.

Startled, and altogether disappointed that the precious moment was over, Ai took the tissues, wiping his face clean and stuffing one into his nose to slow the bloodflow. By the time he looked up, Rin was gone.

\--

The shark didn't know what to do anymore. What just happened? Did Nitori really kiss him? Why? No, it had to be his mind playing tricks on him. Of course it was! He had given in! He had tasted the _blood!_  He smelled it, and gave into his instincts. Or did he? He hadn't bit him until the last moment, and he didn't even realize that he bit Ai until he tasted the blood from his tongue inside his mouth.

_Fuck, fuck, FUCK._

The last thing he wanted to do was admit what just happened to himself, let alone to anyone else.

And yet, somehow he found himself sitting on the beach, phone in hand, telling someone else everything that transpired over the course of the day.

"I don't know what to do," he sobbed. "That dragon said his injuries weren't serious, but I feel like he just said that to make me feel better. Even worse, I bit him of my own volition later! I know I wasn't angry _that_  time! I was completely calm!"

On the other end of the line, Sousuke's voice was calm. It sounded as though he had expected this to happen. He just hadn't said anything because he knew telling him would make Rin cry. "You don't want to hurt him again."

"Y-yes..." Rin mumbled, hugging his knees to his chest pitifully. He missed his tail, but right now wasn't a good time to sit in plain view, pulling at one's own fins for comfort.

"And you trust me to know what to do to fix the situation."

"Yeah..." he said with another choked sob, rubbing his eyes. "The dragon says he has everything under control, but another outburst like that and he's not going to be able to cover it up. What if I actually was aiming for him? What if I killed him?"

"But you didn't. Remind yourself of that." He sounded almost like he was pleading with him, but his tone remained as assertive as ever. Rin didn't really understand it himself.

"No, I didn't, but--"

"But?" Rin could practically hear his eyebrow raise on the other end of the line.

"....Nothing. I just panicked is all. You're the sea guardian, can't you do something? Please?" Now it was Rin's turn to plead. He wondered if he had even heard him, as it was quiet for a minute, and he swore he could hear Sousuke hum.

"Oh, I thought you'd never ask. I'll make the arrangements and be there soon." 

**Notes for the Chapter:**

> Sorry about the super-delay in posting this chapter. I don't really have an excuse other than my lack of Baja blast and way too many upsetting instrumental songs on my pandora station.
> 
> I also have a "bad end side story" that I'm going to write as an alternate ending after chapter six or seven, but it'll be pretty dark and not quite Rintori, because it's what happens if he doesn't get together with Rin. I'll be posting it as a separate work once more of the main story has been posted here. (It'll be very nsfw and horrible I'm so sorry in advance.)


	5. Chapter 5

The following day was Saturday, and Ai decided that there was one thing he needed: answers. Rin was either out for the day or avoiding him on purpose, or some combination of the two. It would be four days before he was allowed to return to practice, in spite of his protests and repeatedly reassuring everyone that he was fine. Rin couldn't seem to make up his mind on whether to act overbearing towards Nitori, or avoid him entirely. Ai didn't see him at all on Saturday, but he refused to leave his side on Sunday, fussing over every little sneeze, every time Ai needed to get up to pee or to get water, not even letting him fetch tissues or a pencil for himself. By Monday, however, he was gone again without warning.

Since he was officially excused from classes for the next few days for a "sports injury," Ai chose to do some research. The story Mikoshiba gave the school administration was that he slipped on a wet floor or something; Ai never saw it for himself, but he needed to rest until it was "safe for him to walk on 'injured foot.'" With lots of finger air-quotes for emphasis. He borrowed a stack of books about the ocean and marine life from the library, and sat cross-legged on Rin's bed, (Rin refused to let him climb up to his own bunk) browsing and taking notes.

He felt it would be a bad idea to ask Rin about what he had overheard. One reason being that he was sure he had heard something that he wasn't exactly supposed to hear, and the other reason being that Rin was very... emotionally charged on the subject. Not to mention, if they _were_  aliens, would they try to wipe his mind or put a probe in him or something? Wasn't that just the kind of stuff from cheesy sci-fi movies? _Er, probably not._  That said, it was about as plausible as any other theory he had on the subject. His only other theory being mutant sea monsters, but to him both ideas still sounded like corny low-budget horror flicks. The thought was funny, at least. _Evil Sea Monster Mutants from Outer Space!_

He sighed, closing another book. He didn't even know what he was looking for. All he really had to go on was "seadweller," and "top of the food chain." Orcas seemed like they were the top, deadly enough to eat seals and sharks, even attacking large whales and sharks for fun. Some sharks were pretty up there too, but. Ugh, these were all just big mammals and fish! As if he was going to find anything that looked like a person anyway. The closest he had to that was that manatees and dugongs had been mistaken for mermaids, but that was about two hundred years ago, and that wasn't enough to ho on. This was completely pointless research. Maybe he _had_  dreamt it all. Kiss and everything.

He was finally able to put it aside when one of his classmates arrived at the door, bearing his missed assignments for the day. He spent the next few hours studying and catching up on his class notes, until Rin returned from practice.

Nitori greeted him with a weak "Welcome back, senpai!" and was greeted with nothing at first.

Rin just sighed, dropping his bag on his bed. "Aiichirou."

Ai straightened up. "Yes, senpai? What's up?"

"We can't be roommates anymore."

"Wh-what?" he stammered, taken completely off-guard by the sudden declaration.

"I said, we can't be roommates anymore." It was obvious that he was trying to keep his voice even, but Ai could see right through it. Rin was probably the most emotionally expressive person he had met, after all.

"But why? Do I toss and turn too much at night and make too much noise? Am I too messy? Do I stay up too late? I could--"

Rin held up a hand to cut him off. He was distinctly avoiding the topic of the kiss from the other day, trying to put it out of his mind. Ai, on the other hand, just looked a mixture of bewildered and hurt, and it pained Rin to look at him. "No. I'm not going because I have any problem with you, It's because I threw you into the pool," he lied. "Even if none of the teachers find out about it, it's still a bad idea for me to stay here."

Ai's heart sank. Rin really didn't want to stay here? He thought Rin was finally warming up to him, and wasn't annoyed by his presence anymore! Rin at least seemed to be broken up by the decision, like he didn't want this either. He had no idea of Rin's true feelings on the matter, only that he was definitely masking them somehow.

"I guess so..." he murmured. "I'd still like to be your roommate..." His voice was hushed. "Um, about Friday?"

Rin froze. "What about Friday? At the pool? It wasn't your fault. It was my fault. I got angry over something that shouldn't have been a big deal."

"I-I guess..." Ai let his voice drop to a whisper. "But I meant um, after."

Silence. Neither of them actually wanted to broach the subject.

"...After?" Rin choked.

Ai opened his mouth to apologize for the kiss, but the words left him. He'd be embarrassing himself if it did turn out to be a dream, but at the same time, he really did want to apologize. It _had_  been pretty gross, he hated the feel of a nosebleed, but the kiss had been so wonderful, and he didn't want his memories of it to be soured just yet. He scolded himself inwardly for being so disgusting, and instead glanced up at Rin.

"N-nevermind."

They didn't bring it up again for several days, something for which they were both grateful for.

\--

When Ai was finally able to return to practice, he decided that the best person to give him answers about what had really happened was Captain Mikoshiba.

Mikoshiba, however, seemed like he didn't want to talk about the subject. In fact, he was dodging any questions his junior had left and right. But, if there was one thing Ai wanted, it was answers, and he wasn't about to just give up without any. Seijuuro was the one person who could tell him what had actually happened, and what was a dream. There was the chance that he could lie, but Ai would figure that out when he got to it. He decided he would broach the question as a matter of concern. Dream or not, _something_  more than a simple shove into the pool had to have actually happened to make Rin act so strangely.

Seijuuro, however, had "mysteriously" become man of many obligations, and didn't seem ready to talk about it. When he approached him before practice, he said he was busy and had to do extra pull ups to work off his extra-calorie lunch. On their water break in the middle of practice, Nitori approached him again, only to be told he was busy re-evaluating the entire team's workout and diet plans. He then rushed off before Ai could get another word in edgewise. After practice, he tried again a third time, but Seijuuro saw him approaching, and quickly began to toss his things in his duffle bag. He tossed it over his shoulder and made to leave, when a single silver chain with a small pendant fell out, clinking to the floor.

Aiichirou picked up the chain, holding it up to the light. "What's this?" he asked, trying tomake it sound as though he was wondering out loud, but mostly to garner the captain's attention.

Seijuuro froze, turning around slowly. "Oh! That's mine. Just something." He made to reach for it, but Ai pulled away, just out of reach as he did

"Oh? it is?" Ai purred. He knew exactly what it was. Anytime he wasn't swimming, he wore it around his nec. He'd fiddle with the gemstone, rolling it between his fingers as he supervised races. When he first got it, he proudly showed it off to the entire team, except Rin. It was a present from Gou Matsuoka, his girlfriend.

Rin's sister.

Literally everyone on the team knew about their relationship, except Rin himself.

Now that Ai had the opportunity, he was able to admire how nice it actually was. The silver chain was thick and untarnished; obviously Seijuuro was taking good care of it. The pendant consisted of a teardrop-shaped red gem, looped through one of the center links. Ai didn't recognize what sort of gem it was, maybe it was a garnet or a ruby. "It's really pretty," he said, half to no one in particular, as if he was the only person in the room.

"...Yeah. It's got more sentimental value to me." Seijuuro reached for it again, and Nitori yanked it away a second time.

"Oh! This was a present from Gou, wasn't it? It looks really expensive," he mused. Seijuuro's face went white as Ai continued. "Maybe I should tell Rin. You know, his sister _is_  giving nice presents to his friends, and all."

Seijuuro looked down at him, and suddenly Nitori felt really ridiculous. He wasn't exactly good at coming off as imposing or devious, and all in all, the entire scene was pretty silly. That, and despite Mikoshiba being twice his size, he had an absolutely heartbreaking pupply face, which was causing Ai's self-titled "bad guy resolve" was to rapidly crumble.

He sighed, handing the chain back to him. "Please," he pleaded. "Just tell me what I want to know, it can't be too bad, right? I'm worried about Rin. I want to know what really happened." He pushed himself into the doorway, hands against the edges of the doorway, as if implying he would somehow be able to stop him from leaving if he didn't have answers. "I....I was awake when you guys thought I was unconscious. I heard stuff. If it's really important to keep a secret, you don't have to tell me, but like I said, I'm really worried about Rin."

Mikoshiba said nothing at first. He took the chain back this time, slowly securing it once more around his neck. "I think it's about time you knew a few things. I've kept you in the dark long enough." He pursed his lips. "Come, we should find somewhere private."

\--

They sat on the roof of the school, watching the sun set. This place was actually a popular hangout for students to take lunch during the day, and a haven for those who would dare to skip their classes, but in the evening it was always empty. Ai leaned against the chain link fence on one side, feeling the wind against his face. Seijuuro lounged on one of the benches, running his fingers through his hair.

"Okay, so exactly how much did you hear?"

"Everything. I think. Weird stuff. I blacked out kind of, but I could hear voices talking by the pool, and again later in our room."

The redhead groaned, but he knew he had a lot of explaining to do. Now was as good a time as any. "You're sure you want to know?"

Ai didn't hesitate. "Yes."

Seijuuro exhaled. Somewhere nearby, birds were chirping to signal the end of the day. The soft breeze stirred the leaves on the school grounds enough to cause a faimilar rustle, but if he closed his eyes, it almost sounded like the sound of waves. "Lots of people you meet, especially in a place like Japan, are creatures of the sea, who have come to live on land," he began. "Sometimes they stay on land their entire lives, but usually they eventually return to the sea. Japan, being an archipelago, attracts lots of temporary citizens from the ocean." He paused, studying him for a reaction before continuing. "Rin, for example, is a white-tipped reef shark."

"A shark? Like a fish? Seriously?" It sounded insane, even repeating it out loud. _Well, at least they're not aliens._

"Well, not a shark like the sort you've seen. Think of him more like...what you would know as a mermaid? Except male, and minus the singing. Almost all fish you meet are akin to merpeople. And actually, fish isn't technically correct. There are lots of mammals too. Fish is just sort of...an umbrella term."

Ai chewed his lip. "So....Rin is a merman? And he has a shark tail?"

"Not just a tail," Seijuuro corrected, surprised that Ai was actually accepting this. The kid looked like he was in a state of disbelief, but somehow he still felt like telling him would be the right thing to do. In all of his centuries of living, his gut instinct was never wrong about man or fish, and he knew Aiichirou was a good kid. He could trust him. "Look, biology was never my forte. If you saw his true form, he'd have claws, gills, a tail, and fins across his back. He's a predator of the ocean," he sighed. "I'm not telling you to stay away from him, I'm telling you to be careful." He hesitated, before laughing a little. "But uh! That's not my place!"

The smaller swimmer sat there for a few moments, picking idly at his nails as he tried to take it all in. He wasn't disinterested; to the contrary, he was focusing on his hands so he could keep reminding himself that this wasn't a dream. Granted, even if it was a dream, it was a very real possibility that Seijuuro was crazy. Then again, he wasn't the only one Ai had overheard saying these outrageous things. It also made sense--in a weird, roundabout way. Rin's constant obsession with bathing, staying hydrated, his avoidance of blood, and his odd behavior, it all could be explained by Rin being a shark? "I'm not scared of him, if you're trying to scare me."

The captain smiled, ruffling his hair. "Nah, I'm not, really. He's just used to getting what he wants. See, underwater society is kinda different from society on land.Our culture is ranked in terms of the food chain. The lower on the food chain someone is, the more... erm... subservient they have to be to more carnivorous or more powerful creatures. Lower fish are instinctively _obligated_  to do what their superiors say, but those higher have the responsibility not to abuse that power. At the top are the predators, like orcas and some sharks, who only have to bow to the guardians of the ocean. Below them are dolphins and carnivorous fish, and so on and so forth. My point is, Rin's place on the food chain means he's used to people doing as he demands, so he can be a bit..." he trailed off for a moment, tilting his head. "What's the word...petulant? When someone like me won't take his shit." He chuckled. "Usually someone as high on the food chain as him would have a companion, someone to keep him in check, but for some reason he's a bit too independent to think he needs one. Or a shiver, for that matter."

Aiichirou swung his legs back and forth, still trying to take it all in. "Wait, you know about all of this stuff, but you don't have to listen to Rin? What are you, really? Does everyone know about this stuff but me?"

Ai watched as the captain's chuckle evolved into a full-blown laugh. "Well, no! Not at all! Seadwellers are very good at keeping our identities secret from humans, and part of that is because most humans don't even believe something like us could exist in the first place. We just happen to be the swim team for a prestigious school, so...it's only natural that our group would include a few fish. But me? I live outside of their societal ranking." He went silent for a moment, gazing up at the clouds. "I'm a water dragon. My power comes from the ocean, which is why I was able to heal you when you fell in the pool."

"A dragon? Really?" His eyes widened.

"Don't look so impressed! You would probably recognize me by my much, much smaller and more common relatives, who you would know as seahorses."

"Really?" His eyes lit up. "Could you show me? Is it safe for you to live out of water?"

"Heh, I'm fine. But, not right now. Staying on land is tiring for me, but I like this human form. Humans are fun to be around!" he answered with a grin.

"Yeah, but. You never answered my question before. What can I do to help Rin?"

It was then that Seijuuro sighed, his grin fading. "There's not much you can do right now. You could say he's at war with his instincts. If you wanted to help him beyond just being a good friend and supporting him, you'd have to trade something to a sea guardian, I think."

"A sea guardian, huh? And you're not one?"

"Of course not! I might be a magical being, but I'm no sea guardian! That's too much responsibility and not enough fun!"

"Huh..." Aiichirou's face fell. This new world of fish he was learning about was much more complex than he expected. How was he supposed to find a sea guardian? "Where can I find--" he heard the door behind them swing open, interrupting his thoughts.

The person standing in the doorway was none other than the redheaded first-year who had beaten Ai out for the spot in the relay. "Captain, there you are, I finally found you."

Seijuuro looked up, his serious expression melting into his trademark grin. "What''s up, Kagami?"

He ruffled his hair with his fingers, eyes everywhere but the captain's gaze. Not that Ai blamed him. Seijuuro was an intense guy, after all. "I want to trade off my spot in the relay."

He raised an eyebrow. "May I ask why?"

"I'm training for the basketball team anyway. I'd rather do that, and..." he paused, eyes darting between Ai and the captain. Seijuuro nodded, and Kagami hesitated before continuing. "After Rin's outburst, I'd rather hand it off anyway. I don't take shit from sharks, and I'd rather avoid a fight."

"Someone put you up to this," Seijuuro commented, his tone unmistakably matter-of-fact.

"I don't want to talk about it, but it's the right thing to do. And I want to. So give my spot--" he glanced over at Ai again, "to someone who deserves it."

\--

Rin lay back on his bed, staring at the bottom of the bunk above him. He had _run away_ , he couldn't handle himself. Seeing the blood in the water would have been too much for him. He left Ai when he should have been helping to take care of him. _Ugh, what a mess._  He should have stayed. He shouldn't be avoiding facing Ai. It was immature. Moving out would help. He'd be with someone else, maybe another human, who wouldn't be such a threat to his well-being.

_Yeah, another human to kiss like that. Not some bloodthirsty shark._

He had been replaying that moment over and over in his head, trying to pinpoint the exact moment the otherwise euphoric kiss went sour. He didn't remember biting him, but his senses were already overloaded from the scent of Ai's blood and the nosebleed. Well, the nosebleed was probably his fault anyway.

He had pulled a dehumidifier into the tiny dorm room after toweling Ai as best he could with some of his teammates. After wrapping him up in towels and blankets, they wanted to be sure he wouldn't become hypothermic from being so wet and suddenly moved into air conditioning. The dehumidifier helped, but it also dried out the room ridiculously fast. The dry air was probably too much for him.

He didn't even remember who initiated the kiss, just that it _happened._  His head was spinning from the smell, and the feel of Nitori's lips against his own was overwhelming. He had tensed up, wanted to react on every fiber of want and desire he had been suppressing the entire time. He wanted to jump on the boy, ravage him, sink his teeth into his skin and draw him in, marking him as his property. _Ugh, it was so sick and wrong to take a human like that, Seijuuro was right._  He had to get himself under control, and fast. The last thing he wanted was to hurt Ai.

He was jolted out of his thoughts by a knock at the door. He rolled out of bed, glancing over at Aiichirou's desk. Had he lost his key? He pulled his hair out of his face as he opened, the door, no doubt looking as exhausted as he felt. "Ai, I don't want to talk about this right--"

He cut himself off mid-thought as the person on the other side of the door was not the short first-year he expected, but a tall, muscular boy with short, dark hair and bright eyes. Rin bit down on his lip. Ai's eyes were bright as well, but they were bright like the sky, while those belonging to the boy in the doorway were bright like the ocean beneath the sun. The comparison sounded dumb, even in his head, but somehow it also felt oddly accurate.

It was Sousuke.

"Hey, Rin. I'm your new roommate."

**Notes for the Chapter:**

> This chapter had a lot of exposition, I apologize. The next chapter will as well, since it's a lot to explain. Ai is definitely falling for Rin even more than he already has. We're about halfway there now!


	6. Chapter 6

Rin moved out to an empty room the following night and Ai was left alone in their room. He had come prepared with a plan to discuss everything with Rin, keeping the _I-know-you're-secretly-a-merman_  part out specifically and begging him not to leave, but Rin refused to discuss anything. He maintained that it was better for them both, and that he had Ai's safety in mind. Ai retorted by calling it a stupid excuse, determined to call him out on his bullshit, but that only made matters worse, and Rin refused to continue the conversation any longer. After that, he left most of his belongings, saying he'd come to pick them up later.

Aiichirou slept on Rin's empty bed that night, his face buried in his pillow. He kept it pressed against his nose and mouth, drawing in every last trace of Rin's scent. There was a bit of chlorine, salt, sweat, and something warm and salty he couldn't quite place. Did he even have the right to feel this attached to Rin? He knew too little about him, what he truly was, but he didn't care.

He pulled the pillow flush against his face, thinking instead about holding Rin, about being in his arms, touching his hair, his head resting on his shoulder. He imagined Rin was beside him now, his arms wrapped around his chest, his breath at his ear. He thought about kissing him again, and the look Rin gave him the other night. In that moment, those eyes had pierced into his very soul. Even if he didn't know about Rin's true form, he knew that there was something different about him. Ai was tempted to call it unearthly, but it was almost _too_  earthly. It was real, primal, _raw._  It made the hairs on his neck stand on end, and his fingers curl just a little tighter around the pillow in his hands. He couldn't stop thinking about Rin on top of him, knee pressed between his legs, one hand holding Ai's hands down above his head, the other pressed against his chest. Rin would stare at him with that gaze, and bear down on him, kissing him, biting him, dragging him down off of the bed, and into an imaginary ocean. He slid a hand down beneath the waistband of his pajama pants, imagining how Rin would hold him. His mind was racing even as he drifted off, falling into a restless sleep filled with dreams of deep water, sharp teeth and fins, and places he never knew, nor could he ever hope to visit.

\--

Practice was lively as usual, and Ai did his best to focus on his personal training. He was paired with Nishinoya again, who never ceased to yell enthusiastically and erratically shout words of encouragement at his teammate. It made Ai feel guilty about barely paying attention. In spite of telling himself he would focus, he kept imagining the pool was the ocean, and that eventually he'd tire out and sink beneath the surface, into darkness and depths far beyond the reaches of humans. He kept gazing over at Rin, who was sitting on the bleachers, accompanied by a tall, dark-haired and well-built boy Nitori had never seen before. They seemed more interested in chatting with one another than watching everyone practice in the first place. He kept slowing down to watch them, so much so that his teammate even had to yell out to him two or three times, to get his head out of the clouds and get back to practicing.

He gave up long before practice was over, and got out of the pool. He was fully aware of how badly his times had suffered that day, but his mind wasn't in it. He showered and changed out of his bathing suit before practice was even declared officially over for the night. He wanted to confront Rin again, at least to settle this enough that Rin would stop avoiding him, but the taller boy who had been sitting with Rin intercepted him first.

"You're Nitori Aiichirou."

Never in his life had Ai felt self-conscious about his height until that very moment. This boy towered over him, and was built to match. Ai didn't know how to react; he barely reached his chest, and of course, the boy was glaring down at him imposingly.

"Y-yes, that's me."

"I'm Sousuke Yamazaki. We're going to talk. Outside."

\--

Aiichirou was still holding his workout bag when they reached the roof, and he shivered against the wind, zipping up his jacket. He wasn't sure why the other demanded privacy so suddenly, but he had a feeling that this had everything to do with Rin. They stood there for a few moments in complete silence, and Ai shivered again before the other finally spoke up.

"You're too weak."

Ai started shaking his head and sent a glare back at him. "That's awfully rude to say to someone you just met."

"But I'm right, aren't I?" His face betrayed emotion, but it was a mix of feelings Ai couldn't quite interpret. "I watched you at practice today. You're too weak to take care of Rin."

Ai felt a flash of anger flare up within him. Who was his guy to be talking about taking care of Rin? Sure, Rin was emotional, and a whole mix of other things, but he wasn't going to let a stranger just talk him down like this. He decided to go on the defensive. "Why?"

"I can't tell you."

He was practically bristling now, his hands instinctively balling into fists at his side. _What the hell was with this guy_? "I know about Rin. Is that it? Is it because I'm different from him?"

"You can't give him what he needs. You'll only get in his way." Sousuke countered, interlacing his fingers as he leaned forward. He wasn't in the mood to debate with anyone, much less a human, about Rin's fate right now.

Aiichirou stiffened, raising himself up with as much confidence as he could muster. "I don't know anything about you, Sousuke Yamazaki, but you don't own Rin. You're not his keeper." Sousuke didn't even flinch. Ai was visibly frustrated as well, even if he had been trying not to let his emotions get the best of him. Who the hell was this guy, and why did he suddenly decide he could barge in and make all of Rin's decisions for him? Rin could room with whoever he wanted, be friends with whoever he wanted, and maybe even kiss whoever he wanted! It made his blood boil, but he let his voice drop. "But...you're right. I don't know what he needs, so I can't give it to him. But! Rin is really important to me!"

The other didn't seem to react at first, choosing only to watch Ai admit that he was wrong, and that in reality he didn't have the ammunition for an argument like this. Then, after what to Ai felt like an eternity of silence, he laughed. "Heh, fine. It sounds like you really do have his best interests at heart. I wasn't going to, but I'll help you. Just keep in mind, I'm doing this for Rin, not for you."

Ai glanced up at him, then back at the floor, then up at him again. Had he heard that right? First he was too weak, and in Rin's way, but now Sousuke was going to help him? "Wait, what?"

"You heard me. I'll help you. I'll make a deal with you to help Rin, and you'll be his guide." He was perfectly calm, as if he were discussing the weather, or a business transaction, and the matter had already been decided in his favor.

"What sort of deal? And hey, wait! Don't act like I've already agreed if I haven't heard your terms. You said we're both in this to help Rin, but I have to make some sort of deal with you?" _What was he up to? What was this guy planning?_

Sousuke was beside him almost instantly. "Rin needs a guide, a companion or a small fish to show him the way until he takes a mate. It could be almost anyone, but Rin refuses to, probably because of his misplaced attachment to you. Without someone to alleviate his excess aggression and calm him, he's stepping out of line. He knows he's in my ocean, he plays by my rules, and he still acts so self-destructively. So you," he explained, "you will act as his placebo."

"But you just told me I couldn't--" Ai attempted, but Sousuke glared down at him, and the smaller boy backed off.

"My ocean, my rules." Sousuke asserted, producing a small, dark vial from his pocket. "I am the guardian of the Southern Pacific Ocean, and my denizens will abide by my rules. You, a human, will be his guide, but to do so, you do need to at least not be completely pathetic. This," he indicated the glass vial between his fingers, "will help with that. It's compressed brine water, from the ocean floor. If you've ever wondered how pools can exist underwater, consider this a small piece of one. Seadwellers who live on land usually keep a jar or a vial like this with them It restores their powers, keeps them healthy, and allows them to maintain their human form without having to drink water constantly. For a human like you, it will have a bit of a different effect."

"And that would be...?" Ai asked, cocking an eyebrow.

"I'm _getting_  to that. Drink a bit of this, and for you, it will make you more like a fish. All life comes from the sea, after all, so it will increase your ability to swim, hold your breath, and for many sea creatures, you will be able to see some of their fins Some can hide their fins well, but you'll smell the ocean on them."

He took the vial delicately, tracing the braided rope around it with his fingertips.

"It has limits," Sousuke continued. "The more filled the bottle is, the faster it will refill itself. As long as you leave one drop, it can refill itself time and time again. The more you drink, the more potent its effects will be. Once you've emptied it, it's gone."

"So...what's the catch? Other than it having a limit, he asked, rolling the glass between his fingertips."

"Well, drink it all, and you become a part of the sea. In terms you can understand, you belong to me."

Aiichirou made a face. "How very _Little Mermaid_  of you, is that supposed to be charitable?"

"You're going to agree to it anyway," Sousuke replied flatly. "I'm giving you a choice, but I know you'll make the right one. Here, I'll even give you a handicap. If Rin claims you as his before you drink the whole thing, I'll use my power to free you, but I can't guarantee that I'll be able to return you to normal."

_Ugh, he was right._  Ai chewed on his lip, running a hand through his hair in exasperation. His bangs were getting long again, he'd have to cut them soon. _The terms are ridiculous, this whole THING is ridiculous, but I can't say no. I need to help Rin,_  he thought. He wasn't going to turn down an opportunity like this, even if it was risky. If Rin needed someone, and he could be that someone, he'd jump at the chance.. "Fine, I'll do it. But if I decide this isn't worth it, I'll give this back to you, and the deal is off. Fair?" He outstretched a hand to Sousuke for a handshake, hoping that the other understood that he was at least trying to stick up for himself. He knew he wasn't in control of the situation, but he refused to be walked on. But, become a part of the sea? What did that even _mean?_   Was it like the western story of _The Little Mermaid_ , where if he didn't hold up his half of the deal, he'd turn into sea foam? Maybe he'd drown? The very thought made him shiver.

Sousuke made to wave him off, but paused, glancing at Ai's hand, and took it reluctantly.

"Very well. And like I said, I'm doing this for Rin, not for you. Don't mess it up."

\--

The next morning, Rin still hadn't returned to collect his belongings. Ai suspected that he was still avoiding him, but he decided that he would wait for the right moment to approach Rin again. He had a plan for how to defuse him, but first: class.

He dressed and prepared for class as per usual, and paused when he noticed the vial sitting on his desk, exactly where he left it the previous night. The fluid inside seemed to sparkle in the morning sun, but the water looked dark, too dark to see through. He picked it up delicately, turning it over and over in his hand. He uncorked it, and instantly his nose was greeted with the smell of the ocean, as if someone had walked in and dumped a bucket of seaweed, sand, and saltwater on the floor directly in front of him. He raised it to his face, tasting the top with a nervous lick. Yeah, it tasted like regular salt water, just slightly more bitter and fishy. He took a small sip, forcing the bitter concoction down his throat, and re-sealed the cork. The braided rope secured below the lip was long enough that he could probably wear it around his neck if he wanted, but he decided it would be safer in his bag.

He rocked back and forth on his heels for a moment. Well, he didn't feel any different just yet. Maybe it took awhile to take effect. No matter, it was time for class anyway.

\--

In Ancient Civilizations, he sat near the back, by the door. He zoned in and out of the lesson, thinking about Sousuke's words, when something caught his eye. The window was open, and near the window sat a tall blonde whose hair blew in the wind. It wasn't his hair that had Ai's attention, though, it was the shimmer coming off of his back and arms. It looked almost like...stripes? Spines? Those had to be fins! They were translucent, as if they were a projection around his body, rather than something that was physically there, and Ai couldn't stop watching them. They glittered in the sunlight, but were just evanescent enough that Ai knew they weren't actually tangible. He tore his eyes away and forced himself to stare at his notes. The lines on the page crossed and blurred when he stared too hard, so he let them wander once more, pointedly _not_  paying attention to the boy by the window.

He barely, if ever, noticed the boy who sat in the row next to him, but today he seemed...different. He was a quiet, messy-looking blue-haired kid with a seemingly-permanent puppy-like expression who was rarely called on. Come to think of it, he hadn't heard him speak all semester, aside from answering whenever the teacher called roll. Tetsuya Kuroko, that was his name, wasn't it? He was swinging his feet idly, slowly, but it wasn't the movement that caught his attention this time. His feet seemed to be outlined by something. Something larger than a normal foot, but long and flat. Wait--were those flippers? They looked dark, but like they were covered in some kind of white fur.

He shook his head, then looked over at him again, trying to avoid looking like he was staring. He was sure a completely dumbfounded look had plastered itself across his face, but he reassured himself that if he wasn't going completely crazy, that what he was seeing were the fins Sousuke had been referring to. The teacher didn't seem to notice, at least, and instead droned on with her lecture.

"As we see in _De Natura Animalium,_  the writer Claudius Aelianus weaves cautionary tales about creatures of the ocean. In one story, the nymph Okyrhoe fled from the god Apollo, but was only able to escape with the aid of a sailor named Pompilos. Pompilos moved her from Miletus to Samos to elude the god. Upon discovering that the nymph had escaped, Apollo was so angry that he turned Pompilos into a pilot fish. Many of the stories in this compendium act less as a beastiary and more..."

As the lecture went on, his classmate had _definitely_  noticed him staring at his feet. When the teacher's back was turned, he leaned over.. Are you okay?"

"Um..." Ai whispered.

"Hey, did you get the spot in the relay?" he asked.

Nitori blinked. "Um, no, but Kagami offered me his."

Tetsuya smiled. Well, if he could call it a smile. It seemed more like a satisfied hum than anything else. "Good. You should take it."

"Wait, how do you--" the teacher turned around to say something, and Nitori thought better of speaking again until their next class break.

When they did finally have break, he pulled Tetsuya aside. "How'd you know about the relay?"

The other didn't seem to react. He hardly even blinked. "I put Kagami up to offering you his spot. He's my mate, after all."

Ai was taken aback. "Wait, he's your... mate? Like boyfriend?" he lowered his voice again. "Like...sea boyfriend?"

"Sort of, but also not really. We're much more mutualist. It's more platonic than romantic. You're being awfully direct." Tetsuya deadpanned.

"Sorry. But um... your feet..." he clicked his tongue softly. "You have flippers?"

"You've never seen a harp seal before?"

Oh. Right. Seeing people's fins and stuff probably would make other sea creatures think he was a fish or something, too. _Act natural, play it off, or something._  He reminded himself, but his classmate's stare was chilling. "Um. No, sorry." he mumbled apologetically. _Smooth._

\--

By the time classes were over for the day, Nitori had two more sips of the vial (it had refilled completely by lunchtime), and was on his third bottle of water. He had also roused up the courage to ask Rin for the rain check they had on the aquarium. He hoped it would be a good way to get Rin to relax a little, and maybe work out their misunderstandings from before.

He was ready to greet Rin outside his classroom, and waved excitedly when his senpai emerged, bag slung over one shoulder. "Hey, senpai!"

"Oh, Ai." Rin seemed caught off-guard, nodding his greeting to him. "I already told you, you can't change my mind about moving into a new room."

Ai shook his head, bounding up to him. "No, actually! I came to ask if you were free after class today! We could finally make that trip to the aquarium that totally failed the last time we tried."

"Oh, um." Rin seemed to be avoiding his gaze. "Sure."

His eyes lit up. "Great! Can I meet you at the bus stop in an hour?"

Rin's eyes darted from Ai to Sousuke, who had emerged from the classroom behind him. Huh, it seemed like this guy had transferred into Samezuka after all. Ai supposed he was making good on his promise (or was it a threat?) to watch Rin closely. Well, he'd show him. He was going to cheer Rin up, not for Sosuke, but because he wanted to. He was determined to make Rin smile.

 

**Notes for the Chapter:**

> Now we're finally getting somewhere.   
> Rin and Ai finally get to go on their aquarium date next chapter. I hope you're as excited as I am!  
> Thanks so much for sticking with this fic so far! I generally don't do well with longer stories, and this one may only get finished because I have the entire thing plotted out in advance. I'm going to crank out as much as I possibly while I still have steam for this story, so I'm really going to make a solid effort to finish it. As always, thank you for reading and I'll see you next chapter!


	7. Chapter 7

That afternoon, they managed to make it to the aquarium without incident. After they had gotten lost last time, Aiichirou had memorized the real address, determined not to forget it, or the way to get there. Rin seemed as unenthused as ever, grumbling under his breath about "fish in tiny plastic containers," until they made their way to the ticket window. In spite of all his complaining, he couldn't help but smile at how excited his companion was. He didn't even pull away when Aiichirou's fingers interlaced themselves with his. Instead, he instinctively pulled them even closer to his own.

The first room they entered was a walkway filled with projections of bubbles on the walls. Rin was about to advance to the next room without as much as stopping for a moment, but he caught a whiff of seawater from somewhere (but where, he couldn't be quite sure), and paused to watch them dance across the walls. Somewhere in the room a speaker played bubble sounds, at which he fought back a small chuckle.

Ai must've noticed that he stopped, because he paused, instinctively tightening his grip on Rin's hand. Rin made no move to pull away against his better judgement. Instead, he drew in a breath, recalling the feeling of water against his gills. He watched the blue lights and bubble projections warp and distort out of their recognizable shapes when they danced across Ai's face.

He closed his eyes, remembering what it was like just to sink down into the water, letting the current pull him along. If he rolled onto his side, he felt he could sleep like that, even if accidentally rolling onto his back meant complete and total vulnerability. He felt no need to worry about that. If he did, Ai would protect him. For an instant, he could open his eyes and see the sun dancing across the surface far above.

"Senpai? Are you okay?"

Rin's eyes snapped open as he was brought back to reality, and he realized Ai was looking up at him, his eyes etched with worry.Rin smiled, further interlacing his fingers with Ai's. "Yeah. Don't worry."

"Do you want to leave? I'm sorry I dragged you back here..."

But Rin shook his head. "Nah, don't worry about it. I I agreed to come. Let's go see some fish."

The first room that contained actual fish tanks was lined with cylindrical tanks, each containing a different kind of small tropical fish. They were brightly colored, but hardly interesting to Rin. He'd seen plenty of them hundreds of times before, in huge schools and swarms along the edges of reefs, but Aiichirou was amazed by every single one of them. He pressed his fingers to the glass excitedly, but was polite enough not to tap, pointing out each of their patterns and colors. He stopped every few paces to talk about different fish he'd seen in movies and what parts of the world they hailed from.

Rin listened, letting him talk. Some of his information was wrong, but so was some information on the plaques beside the tanks. For the most part, it would be right except for the occasional migration habit, or portion of a diet. Upon reading them, Rin realized he hadn't known just how perceptive humans were about their oceans. _And yet they still have no idea creatures like me exist,_  he thought. He wondered briefly why Aiichirou would be so amused by tiny fish in tanks, until he realized Ai had probably never seen most of them before, let alone seeing them in their natural habitats. _If only you knew. You wouldn't be so amazed by a couple of clownfish. I could show you a reef so beautiful you'd cry._

He let Ai drag him to the next room, and down a dimly lit ramp. This room was full of supposedly "dangerous creatures of the deep," including poisonous pufferfish, lionfish, barracudas, and moray eels. Ai kept laughing at the way the eels appeared to be "breathing," Rin explained that having their mouths open wasn't actually them breathing, but their way of circulating water around them to keep water moving over their gills, but his kouhai was giggling anyway.

"Aw, come on, senpai! They look like they're just gasping, then making this face over and over!" He puffed out his cheeks, then opened his mouth over-dramatically to make a motion like he was sucking in a giant breath. "It just looks really silly!"

"Well, you would too, if you had to do that," Rin explained, raising an eyebrow.

"Yeah, I guess so," he smiled. Rin found himself smiling back. He was actually enjoying himself.

In a tank near the back was a giant crown-of-thorns starfish. Rin blanched, disgusted just by looking at it. _Humans keep monsters like this?_  If anything, this really was a "dangerous creature of the deep," not just a carnivore. Ai read off the little plaque beside the tank, which explained that the barbs of the starfish were poisonous, and regrew if broken. If even a single one of their legs was left alive, the entire creature could regenerate. They eat coral, leaving scars and bleaching reefs white, and the toxins they leave behind make it difficult for coral to regrow. "So, something like this isn't um..." Ai looked over at Rin for a moment, then back at the tank. "Do they even have predators? Creatures above them on the food chain?"

"Not really. They're not the biggest guys in the ocean, but I'd call them the worst. Think about it this way: they don't eat fish, but they destroy their homes and do nothing in return. Most predators act more as population control, and smaller fish have their own ways of fighting back, like the spines you saw on the lionfish, if a predator gets too greedy." Rin explained. He was trying not to let his own opinion bleed into the conversation, but couldn't really resist. What was the harm of it? Ai had no idea what he was. "In destroying the homes of fish, they drive them out, which also leaves the predators of that area to starve and die. It takes a reef hundreds of years to grow, and one of these can eat a hundred square meters a day, no problem." He sighed. "Humans demonize predators like sharks, and yet creatures like this are scarier, and basically unable to be killed."

Ai fell back from the tank, his fingers gripping tighter to Rin's. "I had no idea. I feel kind of bad for the sharks now." He wavered for a moment, then perked up again. "Hey, I know! Let's go pet stingrays!"

The open-top stingray pool was overcrowded, but Ai was determined to pet one. Rin nearly panicked at first, telling him he could die if one were to attack him, but he relented when Ai explained to him that the stingrays here were all either rescued or raised in captivity, so they lacked the barbs they would have in the wild. That, and most of the people with their hands in the tank were children anyway. They weren't about to attack anyone.

None of the stingrays in the lagoon seemed interested in approaching Ai, even after he bought some food. He kept his hand in the water, sitting as still as he could, but they swam past him without even coming close, time and time again. Rin took pity on him, guiding his hand towards the bottom. "Keep your hand down here if you have food. Their mouths are on the undersides of the front of their bodies, not the very front like most kids think." Ai nodded, doing as he was told. The rays continued to swim by him, disinterested. There were maybe ten other hands in the pool at that moment anyways.

Rin furrowed his brows in annoyance, and leaned over the water, lips just above the surface. "Get over here and let my mate pet you, or I'll tear you open and gut you all," he muttered.

Eight, nine, and then ten rays immediately swam over to Ai's hand, nibbling at the food, and nuzzling against his fingers. He yelped in surprise as they swam over each other to get to him, and laughed when one went so far as to splash him playfully. "Wow, senpai, look! There's so many of them, what'd you do?"

"Nothing," he lied. "I was just getting a closer look myself." He forced out a small laugh, and while Ai shot him a bewildered look, the splash from another stingray distracted him, and Ai was soon back to playing with them, delighted that they came over.

_Dumbass!_  Rin scolded himself. _You called him your mate to them. Good thing Ai can't understand their language, but you've got to stop thinking like that, idiot!_

"Senpai! Touch one! They feel like rubber, but they're also really soft and slippery!" he was giggling. They were attracting quite a crowd now, and Rin had to calm the rays down, promising he wouldn't eat them, (they were gross-looking sea pancakes anyway) and he was more than ready to move on.

"Say, Rin-senpai?"

Rin looked back up at him, surprised. "What's up?"

Ai stepped down from the tank and towards the escalator. It was more like a moving ramp conveyor belt than an escalator, and they both lounged against the railing.

"If I was a fish, what kind of fish do you think I'd be?"

Rin bit his lip. Just what the hell kind of question was that? Did he have any idea what he was asking? Well, no. Probably not in the slightest.

_Something with stripes._  He thought. _I could just see stripes creeping up your stomach and chest, with two-toned scales outlining that adorable face. Maybe they'd trace his sides, emphasizing his ribs and abs. It would be so adorable._

"Hmm, that's a hard question," he mused. "What about an angelfish? Or a pilot fish? Yeah, you're tough enough to be a pilot fish." He grinned at the thought. Perhaps it was just wishful thinking. He hadn't realized it before, but he knew that he wanted a pilot fish of his own, even if he wasn't about to admit it; especially not to someone like Sousuke, who was determined to fuss over him. For mermen, they made excellent companions and sometimes even mates. They could swim alongside their sharks and carry them when they grew tired, lure in prey for their shark to share with them, and keep their skin clean.

Oh, if he had one of his own, he'd spoil them rotten. For the price of bites on their neck to mark them as his, he'd protect them from other sharks, give them all the best bits of his prey, braid their hair, and clean their scales. He'd be sure everyone knew his fish was _his,_  and the most well-cared for in the entire Pacific.

"What's a pilot fish?"

Ai's question dragged Rin back to reality. Ai was no such creature. He was warm and soft, with silky hair that smelled like his apple shampoo and tiny pink toes that wiggled whenever he wore flip-flops. He had a laugh that sounded like bubbles, and wore shorts so short it should be illegal for anyone but him to wear (but god, they showed off his slender legs and perfectly-shaped little ass), paired with monstrously-sized sweaters that sometimes made it look like he wasn't wearing any shorts at all. He had pierced one of his ears himself earlier this year, and kept a tiny silver ring in it to keep it open, but always removed it for class and swim practice. No, Ai was human, and perfectly so.

"I'll show you, if they have any here."

The conveyor opened up into the shark tube, and Ai audibly gasped at the sight above them. The space above them was a domed archway that consisted of what Rin assumed t be super-high density compressed plastic, on top of which was one of the largest human-constructed tanks Rin had ever seen. It was filled with sharks and carnivorous fish of all shapes and sizes. Nurse sharks, zebra sharks, leopard sharks, barracudas, even white and black-tipped reef sharks swam together here. Rin drew in a breath at the sight of so many familiar creatures. He noticed that Ai kept glancing from him, to one of the reef sharks, and then back to him. _No, there was no way he could have noticed._

One of the striped black-and-white fish had shimmied up alongside the reef shark and was swimming alongside it. They were perfectly in sync, and Rin could even see both of their gills moving in time with one another. A true pair.

"That, see the striped fish up there swimming next to the shark with white edges on his fins?" he pointed upwards, toward the pair.

"Yeah, the little one?"

Rin nodded. "Don't underestimate him. That's a pilot fish. They're not super fast, but they swim for miles and miles, just like how you're an endurance swimmer. They guide sharks so they don''t lose their way, help them lure in prey, and keep parasites off of the sharks."

"That kind of fish, huh...?" Ai's voice seemed far away, and Rin shook his head.

"Don't like it? Well. Uh. Don't worry about it. Pilot fish are cool, but don't dwell on it, okay? You're great just as you are, don't worry about what you're not." He let his arm snake around Ai's shoulder, holding him to his side. He was still holding him when they reached the end of the tube, stepping off of the conveyor and into the dark hallway. He nearly jumped at the sound of an excited squeak and the sound of a familiar, high-pitched voice from behind him.

"Yeah, you go, Rin-chan! Now touch his butt!"

"Nagisa, that's inappropriate!" A deeper voice from behind him scolded.

Rin groaned, but a short, scruffy blond boy with a taller, very exasperated looking boy in red glasses in tow was already upon them. The blond grabbed Ai's free hand, grinning as he led them out of the hallway, towards the patio.

"No it's not! Rin-chan was totally getting some! And what a cutie, too! Rin-chan's got a cute boyfriend~" he singsonged. Ai instinctively shrank back towards Rin. Yeah, Nagisa could be pretty scary. He didn't recognize the guy Nagisa was with, though. "Hi, my name's Nagisa Hazuki!"

Ai just stared at him, dumbstruck. "Um..."

But Nagisa was already pouting before he could get a single word out. "Rin-chan! Introduce us!"

They all sat down on a group of round benches outside of the jellyfish exhibit, in an open space beneath a sculpture of balloons arranged into a huge mass of jellyfish. Rin had to resist the urge to rub his temples. "Nagisa, this is Nitori Aiichirou. Ai, this is Hazuki Nagisa, like he already said. And this is um..."

The taller boy straightened his glasses, letting the light from the skylights above reflect off of them mysteriously. _How could he even do that?_   "Ryuguzaki Rei. I have heard a lot about you. Pleasure to meet you, Rin-chan-san."

"Er, my name is Rin, just Rin," he corrected.

"Ah, right. My apologies, Rin-san." He deadpanned.

"No, just Rin is fine. It's weird when people are so formal with me," he attempted, trying to alleviate at least a few of the many, many levels of awkward that had descended upon the conversation.

"Rei-chan is gonna be my wife!" Nagisa declared, as if he was simply sharing his grade on a test or an award he won.

"Please stop saying that," Rei countered, steadying his glasses yet again.

"Is Aiichirou-chan your boyfriend? Or is he your mate? Rei-chan's mine! You can't tell just by looking at him, but he's actually a sel--"

"Aiichirou-san, you said your name was," Rei interrupted, standing up suddenly. "Let's get takoyaki." It was a statement more than it was an invitation. He was trying to get Ai away from Nagisa, if only for a minute or two.

"Oh, um, sure," Ai murmured, allowing himself to be hauled off by the bespectacled teen.

Nagisa turned back to Rin, as if he hadn't been interrupted in the first place, but Rin threw up a hand to stop him, and spoke first. "What business does the prince of the Sea of Japan have here?" he demanded. "I wouldn't expect to see a koi so far from his home."

Nagisa puffed out his cheeks in a pout. "I'm winning my bride."

Rin rolled his eyes. "Sure, whatever."

"Whatever? Hmph! You haven't seen me in months, Rin-chan, and now I run into you by chance with your new boytoy, and you 'whatever' me? _Excuse you._ "

The shark sputtered at the accusation. "B-boytoy? Ai's nothing of the sort! He's--he's just a friend from school! He's only a human, can you at least turn down the sea chatter around him? I'm trying to act at least slightly normal. Normal as in, you know, _human_  here."

Nagisa just waved him off. "Whatever you say, Rin-chan! Just because he's a human doesn't mean he's not your boytoy! I saw you hitting on him in the shark tube. You're totally smitten! I don't blame you, but _I've_  got it better. I mean, look at Rei-chan over there! He's really pretty, isn't he? Without his seal skin, that's actually his real form. It sucks because without it, he can't swim, but if I find it, I can make him my bride!"

"You mean husband," Rin shot back coyly.

"Nuh-uh! I mean bride! The tale goes that if you can find and keep a selkie's seal skin, they'll become your bride!" Nagisa insisted.

Rin groaned. "Nagisa, that's how all seals are, minus the bride part. They're not like normal merpeople, I can't believe I have to explain this to you. For a prince, you sure are oblivious about the ocean."

Nagisa just shook his head. Clearly he wasn't taking him seriously in the slightest. "Nuh-uh! It's an Irish folk tale. You hear that? _Irish!_  How exotic!"

"I'm Japanese," Rei asserted from beside him. He had returned with Ai, holding two sticks of takoyaki each.

Grateful for the distraction, Rin took the opportunity to take the skewer from Ai, smiling and thanking him. He slid over to allow a little extra space for his kouhai, and Ai blushed, reassuring him that it was nothing, it was Rei's idea really, and that he hoped Rin was having a good time.

Ai couldn't help watching Rei and Nagisa in a mix of wonderment and confusion. Nagisa was definitely some kind of fish, maybe a goldfish, or a koi? He had the most beautiful spectacled white and orange fins trailing behind his arms and legs, and a long ridge-like one that trailed down his back and fllowed like a wave whenever he moved. Despite Nagisa being nothing short of terrifying for someone so small, he was one of the most elegant creatures Ai had ever seen. Rei, on the other hand, seemed completely human in shape. He wondered if Rei was one of those fish who hid their fins well, but it didn't really seem like it. He still had that distinct saltwater scent, though.

So they were from the ocean, too. Were all of Rin's friends from the ocean? Listening to them all chat amongst themselves, he thought back to Sousuke and captain Mikoshiba as well. It was in that moment that he truly felt like an intruder in Rin's world.

_Rin was a shark, not a person. Or rather, he was a shark-person, not a person-person._  That sounded dumb, even in his head. Rin probably related more to all of the fish in the aquarium than he did himself. No wonder he complained before they bought their tickets. No wonder being here with him must be such a pain. All of that, and yet Rin had still smiled at him in the shark tube. He laughed at him at the stingray tank. He was smiling now, when they shared this silly fried snack.

_Why?_  He sighed, leaning against Rin, who offered him the rest of the stick. Ai thanked him and shook his head no, more than happy to watch the shark finish the snack off. Beside them, Nagisa was going on and on about something or other, but he wasn't paying attention. Rin's hand was resting on top of his, and he slowly curled his thumb and index finger around Rin's.

"Is there anything else you'd like to do?" Rin asked, and Ai took it as an opportunity to have a bit more alone time with Rin. Which he wanted, of course, but now he felt more like he was in the way than anything else.

"Um, not really..."

Rin smiled at him, standing, but not letting go of Ai's hand. "Well, the takoyaki made me thirsty, so I think we should grab some milkshakes on the way back to the dorm. Nagisa, we'll catch you some other time. Rei, it was nice to meet you. We could uh, all hang out sometime."

"Okay, Rin-chan! If you wanna run off with your boyfriend, that's your choice, but don't be a stranger!" Nagisa answered, practically bouncing in his seat. "Here, Ai-chan! Give me your number! We should text later!"

Ai stared at him blankly for a few seconds, but gave in and agreed to trade numbers with Nagisa. He didn't see the harm in it, and hey, maybe he could ask Nagisa about Rin later.

\--

After they bought milkshakes, they sat in awkward silence on the bus. Ai kept using his cup as an excuse to avoid eye contact with Rin, and every time he looked up, he had to remind himself not to look at Rin's fins. He had stared at them in the shark tube at the aquarium, and it felt a little silly. It was easier to see them now, since he had another sip from the vial from Sousuke when Rin went to the bathroom.

"I'm sorry if Nagisa was a bit... brash. He's like that sometimes," Rin began, clearly attempting to revive the conversation.

"Oh! Um, it's okay. It was nice meeting friends of yours," Ai replied, chewing on his lip. "Where do you know them from?"

Rin paused, then reclined in the bus seat, taking another sip from his shake. "I've known Nagisa since we were kids. My family moved around a lot, so we haven't really uh... kept up that well."

"Oh, well he seems... " Ai floundered for a moment, searching for the right word. "Er... nice."

Rin chuckled. "You don't have to be so nice about it. I hope he didn't say anything to upset you."

"Oh yes, I mean, no! Not at all!" Ai answered with a blush. His mind went back to Nagisa announcing that he was Rin's "cute boyfriend," but he felt like nothing of the sort. Or was he? He guessed what they had today could be seen as a date, even if he had assumed Rin didn't have any interest in him. "Just um. About what he said."

Rin raised an eyebrow. "What about it?"

"Well um, have you ever had a boyfriend before?" he asked, not looking up from his shake.

"No, I haven't." Rin answered with a small sigh. "Why are you asking?"

"Because. I mean. Would you ever want one?"

The redhead hummed a little to himself. "I want one, yeah, but I can't right now."

Ai's heart sank. He should have expected as much. "Why not?"

"I uh...I really need to focus on swimming and..." _And finding your own fish,_  Ai thought. "And my schoolwork. But I wouldn't mind, sometime. Just not right now."

The bus dropped them off near the dorm, and Ai paused near his door, wishing that Rin would just come back in with him and stay there. They could fall asleep to movies and talk about boring stuff like homework, or discuss their plans for Golden Week. It had been so easy to talk to Rin all day, and he loved every moment at the aquarium. Why, then, was it so hard to talk all of a sudden? Rin said his goodbyes, and he reflexively reached out, snatching him by the wrist. "Rin, wait!"

Rin paused, startled at the sudden reaction. "What?"

Ai grabbed Rin's wrist with both hands in a sudden, desperate gesture. "Rin-senpai... if you... ever change your mind. If you ever want a boyfriend... I like you a lot, okay! I'd be your boyfriend!" With that, he reached up, gave him a quick peck on the cheek, and rushed into his room, leaving the shark standing alone in the hallway, staring at the door to the room they had previously shared in silence.

**Notes for the Chapter:**

> Thank you for bearing with me through the long break between updates here! I really have no excuse for keeping these two separated. It turns out that this is probably going to be around 12 chapters (plus maybe an epilogue) instead of the original 10 I had planned out, since a lot more needs to happen before the end. So, it'll end when it ends. I have no intention of leaving this story unfinished! (If you want to keep up with my progress, I post about this story regularly on my twitter: @amurtunacaptor, I'd also love to hear from you there.)  
> Thanks again for reading!


	8. Chapter 8

_"I like you a lot, okay! I'd be your boyfriend!"_

Ai knew he wanted Rin, but he felt that he was just being selfish. Selfish, and Rin felt more unattainable than ever.

For the remainder of the week, Ai decided to focus on practice. Each morning, he would drink half of the liquid in the vial (and by lunch it had completely refilled itself) and have half of it again at lunch.

His times were improving drastically, and he found that he could hold his breath longer and longer each day. By Tuesday, he found that he could swim nearly a quarter of the length of the pool without coming up for air. By Thursday he could make it halfway, and Friday he found he had nearly made it to the other end before he needed to come up at all. Personally, he was beyond pleased with his progress, even if a large amount of it was due to the strange magical properties of the brine water, rather than his own efforts. At this point, he wasn't even sure if he cared. He was happy to be keeping up with the rest of the team, and everyone was proud of him. He felt like it was easier to swim longer, kick harder, and move faster.

The only major thing he found to be an inconvenience for himself was the fact that he felt constantly dehydrated. He was now drinking up to four or five bottles of water a day, and he had given up on buying water bottles. Instead, he resorted to filling them over and over from the tap.

He stood in the shower for nearly half an hour each day after practice, and he found himself wondering if this was how Rin felt, as if he would very nearly dry out each day. No, Rin probably felt it on a much more dramatic scale, so he chose not to make a big deal out of it. Having this newfound power was worth every last bit of water he had to drink.

"You know, it's strange," captain Mikoshiba commented, and Ai jumped, suddenly realizing that it was just the two of them left in the showers. "The sort of effect that drinking lagoon brine has on a human."

Ai stiffened up, caught off-guard by the sudden comment, but Seijuuro seemed perfectly calm as he continued. "I've seen it empower mermaids and mermen to live on land, but for a human, its effects are almost the complete opposite."

The younger swimmer swallowed. "How could you tell?" he asked, lowering his hands from his soap-soaked hair.

"Like I told you, I've been around for centuries. That, and you smell like seawater. Human sweat is salty, but the smell of the sea is different." He smirked. "Don't worry, you're doing fine, and your secret's safe with me. That's not why I wanted to talk to you, though."

"So you're approaching me in the shower? Captain, that's just weird!"

Seijuuro just laughed, completely unperturbed. "I'm inviting everyone who is coming to regionals to participate in a training camp during Golden Week. It's definitely not mandatory, but it'll be a lot of fun!"

_Fun._  Aiichirou tried to imagine what a word like fun meant to captain Mikoshiba. A training camp? His mind conjured ideas of military boot camp on steroids. _Crazy, probably. It'd be weird and impossible._  He could ditch them on Okinawa Island, or worse, some tiny island in the Pacific as far from civilization as they could get on foot, and survive for days on edible leaves and roots alone! Each day, another member of the swim team would be eliminated until there was no one left. Maybe he'd summon some sort of monster for them to battle against, or take them out on a boat into international waters and leave them there, telling them to find their way back to the shore on their own. He'd _die_!

And great, now the captain was staring him down, expecting some kind of response. He had to say something, anything! "I um..."

"Good! I'm proud to have such driven and dedicated swimmers on my team! Pack a bag you can carry, and meet us at the bus stop tomorrow morning, got it? See you there!"

Ai sighed, shaking his head. He briefly wondered exactly what he had just unintentionally agreed to.

\--

Rin was far from happy to be awake, even as he stood at the bus stop on Saturday morning. He forced himself to be a morning person for sports, and sports alone. Fog still hung low to the ground, pooling around streetlights and the reflective surfaces of signs, blurring their colors and casting halos in the dim morning light. He was treasuring the first few minutes before anyone else arrived, when he could still smell the ocean on the breeze and the only sound was that of distant birds chirping. It was times like this that he thought of early mornings at home, before the sun forced its way down through the waves above.

Ai was the second to appear at the bus stop, bag slung across his shoulders, hands stuffed into the pockets of his familiar Samezuka team jacket. He found himself watching Ai out of the corner of his eye as the smaller swimmer rocked back and forth on his heels. "Morning, senpai! You're coming on this trip too?"

"I _am_  in the relay and swim the 100 meter freestyle," Rin muttered. "I didn't know you were coming."

Ai blew a puff of air out of his face, his bangs swooping out from his forehead. "Kagami gave me his spot in the relay," Ai explained. "So uh, yeah, the captain invited me!" he was smiling. "Senpai, I promise I'm going to work hard and earn my spot on the team!"

Rin paused, his mind flashing back to the previous week's events. Seijuuro's team choices, his idiot decision to confront him in front of everyone... and the conversation he had with the dragon after the fact. "You already earned your spot on the team," he replied with a small huff. "You don't have to prove yourself."

The silver-haired boy looked down, sighing at his feet. Rin had only been away for a few days, and Ai's jacket and workout pants obscured his view of Ai's body and removed much of the definition on his arms and legs, but, had he always carried himself like that? Was Ai always so adorable and so _strong_?

"Yes I do," Ai whispered, and Rin opened his mouth to argue, but it was at that moment when the peace between them was interrupted by the enthusiastic greetings of Seijuuro, accompanied by Sousuke, some swim team members, and a bouncy shorter redhead Rin had never seen before (but recognized as another dragon).

They waited for a few minutes for the last few stragglers to arrive before the bus came, and once it did, the team piled on and paid their fares.

Rin wanted to find a comfortable seat near the window to relax against and snooze, but his kouhai slid into the seat beside him, and Rin felt guilty immediately turning away and laying with his forehead against the windowpane.

Mikoshiba waved in everyone's attention and explained the purpose of the trip to the group. Rin was grateful that for once their captain was being mindful of the other passengers and keeping his voice down. In a nutshell, the captain had organized this Golden Week trip to an island as a last burst of training for the team before regionals. He was confident in their abilities to qualify, but he urged them all to push their hardest and do their best. It was admirable how he never mentioned "times," or "winning," just swimming with power and breaking beyond their limits to ascend to a higher level of swimming, whatever that meant. Rin was sure the speech was meant to be inspirational, but at that moment, he was too tired to care. It seemed that Ai felt the same way, and Rin felt a weight against his shoulder, which he soon noticed was Ai's head, eyes closed and his face the picture of exhaustion.

He'd been training so hard at practices recently, and to Rin, the additional effort appeared to be paying off. His times had improved, he had put on some muscle mass, and Rin was proud of him. He slung an arm around the freshman lazily, his hand cupping his shoulder. Ai didn't open his eyes, but Rin could see that he was smiling.

The captain was still rambling on two seats ahead of them, about the regimen for the next three days, where they would be staying how much they would be running, everything down to the last minute detail. Rin knew he was intense, so he wasn't surprised by his micromanaging of their trip down to the minute, but at that moment he also found it difficult to care. He yawned, letting his head rest against Aiichirou's and drifted off into a light doze, hoping secretly that he would find some time during this trip to slink off and swim on his own.

The ferry to the island was quick, something for which Rin was grateful. The bus ride was long and bouncy, and every time he tried to catch a decent nap, something would rouse him, whether it was yelling or a bump the bus hit, or them stopping for food or gas or a bathroom break. The ferry was a relief in contrast: smooth and short. Aiichirou and a few of the other freshman stood at the edge of the deck, leaning over the railing and watching the waves pass by. Rin fought back the urge to roll his eyes. Most of them had seen this sight so many times before. The only thing that was new about it was the people they were sharing it with.

After they checked into the hotel (and he was glad his assigned roommate was Sousuke), everyone changed into workout clothes and stretched before running on the beach. The sun was hot but the breeze was cool and moist from the ocean, and Rin welcomed it.. He dearly missed swimming with his fins and tail, but running like this reminded him that endurance, power, and strength; these things came from his core, rather than from anywhere else. There was a degree to which it mattered, but discipline was equally important. "Discipline," however, was also the excuse Seijuuro had for all of them making the trek up the hill to the hotel on foot while carrying their bags.

After lunch, most of the freshmen and sophomores broke off to play volleyball, which they had somehow managed to convince the captain was a productive part of their training. Sousuke announced that he wasn't going to bother wasting time with a childish game and would rather go back to working out, and invited Rin to join him. Rin hadn't been doing anything important, just sitting in the sand and stretching, so he agreed to go on a run with the brunet.

Rin had a faster pace than Sousuke when it came to jogging, but Sousuke had a longer stride, so the shark had to expel more energy and take more steps just to keep up with him. The wind whipped against their faces, and they ran for a time in silence, listening to the sound of the sand shifting beneath their feet and the waves crashing against the shore. After half an hour, they slow to a walk to recuperate, and Sousuke kept glancing over at Rin, often enough that the shark finally felt the need to say something about it. "What? Is there something on my face?"

His taller companion maintained a straight face, acknowledging his question with a shrug. "No, I was just making sure that you were healthy."

Rin assessed the pros and cons of making a snide remark in response, and ultimately decided to go for it. "Why wouldn't I be? You sure are acting awfully motherly today."

Sousuke scoffed. "Fine, sorry for worrying about your well-being," he teased. "Say, we're out of eyeshot and earshot from the team," he nodded to Rin, tilting his head towards the water. "If I know you, you've been itching for a dip."

Rin glanced around, double-checking that they were safely out of sight and smirked, peeling off his jacket and tee shirt, discarding them on a nearby boulder. He pulled at the waistband of his pants, yanking them down to reveal his jammers underneath.

Sousuke wore a smug look, even as he stripped, and the shark was sure to give him a pointed glare, if only to tease him.

"What?" Rin demanded. His expression remained neutral as Sousuke took a step into the surf, until he was up to his waist, and hooked the top of his thumb over his waistband.

"I meant a _real_  swim, not just a dip." the gesture was almost lewd, but Rin knew better. He needed no second bidding, and his eyes it up at the suggestion. He took his jammers off, jogging a few paces, and dove into the surf.

He caught up with Sousuke quickly, who had to reach deeper water before returning to his true form. Rin, who was more accustomed to the shallows, dipped his entire body under, and came back up briefly, tossing his hair back. Though his head was above water, he could still draw in a deep breath, opening the gills that stretched across the sides of his ribs. He let Sousuke pass him as he headed for deeper water, floating there for a moment; basking in how nice it was to _breathe_  again, with the water flowing around him.

The sky above was clear and blue, with small cirrus rushing by far above on a strong breeze. His mind wandered to how it reminded him now of Aiichirou's eyes, all light and breezy, untouchable and unreachable. _But wasn't the ocean blue because it reflected the sky?_  At least, that was the tale he had heard as a pup.

He rolled over in the surf, giving a strong kick, thinking of home, of his birthplace far from here as his spine elongated, legs fusing and melting into a sharp, powerful tail. His torso stretched and his dorsal and pectoral fins pushed through his spine and revealed themselves along his back and torso. He felt his bones cracking and rearranging in his hands into sharp, edged claws, more hydrodynamic and ideal for hunting and swimming. The most crucial part for him, in terms of masquerading as a human, was focus. It was easy for him to return to his true form; he thought of swimming. He thought of his birthplace, of the thrill and pure adrenaline rush he got from hunting, even the brilliant reefs that made his home. Becoming a human was harder. He had to think about what a human was; fingers and toes, a short, gill-less torso, knees and thighs, ankles and knobby thumbs. But he'd think about that later.

He laughed gleefully, kicking with his tail and slipping farther into the depths, where he found Sousuke waiting. He knew that the sea guardian could assume any form he wanted, but Sousuke's preferred visage of a whale shark merman was oddly fitting, and Rin had difficulty picturing him as anything else. He was significantly larger than Rin, thus the need for deeper water, with a gigantic blue tail dotted with white speckles that reached all the way from the edges of his cheeks, down his back, and to his rearmost tailfin. In size and stature he was intimidating to most any fish, but Rin never found him to be very threatening.

He smirked, swimming right up to the larger merman, bumping against his side with his forehead playfully.

Sousuke raised an eyebrow, circling around and hovering by the edge of the dropoff. He moved to swim out into deeper water, but Rin stopped. "We should stay close to shore," Rin explained hesitantly. "Just in case."

The whale shark nodded in agreement, letting Rin call the shots this time around. The swim was more for Rin's enjoyment than his own, but he was fully capable of enjoying himself in the shallows as long as he didn't accidentally beach himself. That considered, he still wasn't at risk, as he could easily shift back into human form, Rin bumped him again, and he chuckled. "Fine, fine. Want to race?"

Rin's face lit up in the most genuine smile Sousuke had seen from him in what felt like, and probably had been years. "Do I ever!"

\--

Aiichirou sighed, laying back in the sand after an exhausting volleyball match. Regardless of whether Sousuke considered this to be goofing off or not, compared to doing traditional workouts, he was exhausted. His forearms were red and sore from contact with the ball, and his calves were burning from all of the jumping in the sand. As he watched the sky, he could see dark clouds rolling in above them, carried by the strong breeze into what had been a bright, cloudless sky only an hour or so earlier.

He sat there until he caught his breath, his face dripping with sweat.

"Oi, don't tire yourself out!" a familiar voice chided, accompanied by a flying water bottle that would have definitely hit Aiichirou in the face if he didn't dodge it.

"Nishinoya-senpai! Be careful!" Nitori squeaked, picking up the water bottle as he scrambled to his feet.

The second year grinned, volleyball tucked under his arm as he approached and Ai resisted the urge to squint at him. Trailing behind him were flowing red fins (geez, would he ever get used to seeing those), and for a moment, Ai thought to himself how unfitting they were. That was, until his eyes landed on the other's smile, and it clicked. _Duh, a betta fish. Everyone seems to act just like the type of fish they are, huh? For trying to hide their identities, most of them don't try very hard to hide their personalities, either._

"Come on, Nitori-kun! Didn't you enjoy my alternative practice? Pretty brutal, huh?" Brutal didn't even begin to describe it. This guy was tireless. He almost never let the ball hit the ground, diving for it perhaps even more elegantly than he did diving through the water.

"Noya-senpai, I don't think I'm cut out for volleyball. I'll stick to swimming," he groaned, forcing himself to his feet.

"Well, either way, you gotta stick to it! Now come on! It's totally gonna rain any second! Let's pack up the net and get inside with our stuff before anybody else!"

Ai breathed another sigh of near-frustration-but-mostly-exhaustion, and nodded. The sky _was_  getting dark, and they had to get a move on if they wanted to get everything inside before the rain started. He recalled Mikoshiba warning that the weather could change almost instantly on this island, but he hadn't taken the warning seriously. He was grateful that his shorter senpai was observant enough to take notice of the weather early enough that they wouldn't be rained out.

Once the two of them put all of the equipment away and stowed it back in the shed where they found it earlier that day, they grabbed some snacks from the vending machines and went their separate ways, each to their own respective hotel rooms.

Ai sighed as he entered his room; he was completely spent for the day. Unzipping his jacket and tossing it on one of the beds, he sank down with his back against the door. He was completely unable to will himself to move for long enough to reach the bed just yet. He exhaled, listening to the sound of his own breath. Finally, a moment of real relaxati--

"You must be Nitori-senpai!" A bubbly voice announced, and suddenly a pair of hands were on hIs shoulders, his eyes met gold and slicked up red hair. Oh, he saw this kid on the bus. He wasn't on the swim team, was he? He had never met this kid before.

"Uh... hi?" He attempted, blinking blankly.

"You're even cooler in person, Nitori-senpai! My bro told me all about you! You're an endurance swimmer, right? That's so cool!"

"Um. Yeah," Ai grumbled awkwardly, pushing his head back against the door, and the other boy leaned in close, sniffing him, gold eyes bright and sparkling with mischief.

"You smell like seawater, but I know better!" he announced boldly and stood up, reaching a hand out to Nitori.

"I um...." The silver-haired boy defended dumbly, letting the redhead help him up. He stretched, scratching the back of his head sheepishly. "That's because uh, I'm... I'm a pilot fish," he lied. _Holy shit, Aiichirou,_  he scolded himself. _You're such a bad liar, he'll never believe you._

But the stranger seemed completely fooled. "Really? Oh, I can see it! Oh, I'm so rude! Sorry about that! I'm Mikoshiba Momotarou! Above the water, I like collecting stag beetles! Underwater, I like collecting crayfish and sea urchins! Next year, I'm coming to Samezuka academy, too!"

Ai blinked. _Well then._  He hadn't really expected him to just accept it like that. _Wait, Mikoshiba? The captain's brother?_   "But if you're in middle school still, why are you here?"

Momotarou shrugged, finally backing off a little. "My bro dragged me along. He's trying to convince me to join the swim team, but eh. I wanna join the basketball team instead. Swoosh!" He mimicked a layup motion, then flopped back on the bed Ai hadn't thrown his jacket down upon.

Ai opened his mouth to speak, then shut it awkwardly. He opened his mouth again, but this time he was interrupted by a loud clap of thunder. He didn't even see Momotarou get up, but instantly the smaller boy was upon him, arms wrapped around his leg. "I hate thunder," he whispered, as if it would suddenly justify what he just did.

"Uh... huh," Ai managed. He had to take control of the situation. "Let's just come sit over here on the bed... you don't have to be such a wet blanket," he waddled over to the bed, straining against Momotarou's weight until he practically fell forward onto the duvet.

"I'm not a wet blankeeeeet~" Momotarou whined. "I am a sea dragon. I'm awesome! Thunder is just...not awesome."

Ai groaned. It was going to be a _long_  night.

\--

The wind was picking up by the time Rin stepped back onto the beach. He fetched his leggings, tee shirt, workout pants, and jacket from the rock where he discarded them, and the rain started just as he finished getting dressed. It felt like a damper, despite the fact that he was already soaking wet. There was a difference between being wet from the surf and wet from rain. Rain always felt depressing. Now he'd be cold, to boot.

He and Sousuke began the walk back to the hotel, teasing each other about their swimming, or lack of swimming skills when it came to shallow water. Rin didn't have the heart to say he hadn't paid much attention to Sousuke, or his swimming. The entire time, he had been thinking of what it would be like to swim with Aiichirou. Ai wouldn't swim as fast as he or Sousuke, but he imagined the boy meandering along behind him, the sun's rays dancing through the water and distorting across his face beneath the waves. The speed he imagined Ai to swim with was greater than that of a normal human, but just enough to keep up and stay in Rin's vision in his imagination. Imaginary Ai would catch up to him sometimes, nudge his side, and giggle, bubbles escaping his mouth. Maybe he wouldn't say anything, maybe he would ramble on excitedly about something or other, all of it interspersed with excited beckonings and calls of "Senpai, senpai, senpai!"

If even a moment of that was real, it would have been pure bliss.

After about ten minutes of walking, Sousuke stopped. Rin looked up. "What's up?"

"We should be back to the hotel by now. This isn't the way," the whale shark answered grimly. Rin blinked, glancing around at their surroundings. Had he really been so caught up in swimming (and his own imagination, for that matter) that he hadn't remembered where the hotel was? He cursed under his breath. Sousuke was right. He didn't recognize anything here, whether it was the scenery or the buildings.

"Shit," he mumbled, walking up to the road.

"Hey you two, there's no reason to look so miserable," came a familiar voice. Both Rin and Sousuke turned in surprise to see a tall boy in an Iwatobi High jacket standing on the side of the road, holding an umbrella.

"Makoto? What are you doing here?" They both asked in unison.

"Wait, you know Makoto?"

"I'm surprised you know Makoto," they interjected towards each other, voices overlapping.

Makoto just smiled sheepishly. "We should all get out of the rain. So uh, come on? Our hotel is just up over here."

"What do you mean by 'our'?"

\--

"Rin-chan's here! Rin-chan's here!" Nagisa explained, practically jumping on top of the shark as they entered the room.

The room the Iwatobi swim club was sharing was much less luxurious than the ones that Samezuka had rented for its swim team, but it was homey. There were futons for all four of the boys neatly lined up along the floor on one side, and Rin assumed his sister and their manager had another room somewhere else in the hotel. A mat and small table graced the opposite side of the room, and the swimsuits for the entire team hung on a thin line of string, stretched over the doorway, dripping into a metal basin. Until about three seconds prior, Rei had been sitting on one of the futons, until he rushed up and implored Nagisa to get off of Rin, who the blond boy was practically climbing on.

"Rin, I didn't expect to see you here," he commented causally, while prying each of Nagisa's fingers off of the shark's arm individually.

On another futon sat a raven-haired boy with radiant blue eyes and a stoic face who Rin recalled as Haruka. Haru, for short. Haru had found him nearly beached in a tide pool when Rin was still a young shark, and released him back into the water. He seemed decidedly human, but at the same time, he also felt more like the ocean than any other person, man or fish, Rin had met in his entire life.

Makoto sank down onto one of the empty futons, wearing the same soft smile as he always had. He and Sousuke regarded one another anxiously, and Rin pretended not to watch as Sousuke reclined, stretching, and let his head sink down into Makoto's lap. The other smiled, leaning down to whisper something in the sea guardian's ear, and they both laughed.

Nagisa looked to Sousuke, and back to Rin, and then to Sousuke again. "I'm glad to see that Rin-chan isn't cheating on Ai-chan!"

Rin sputtered. "I--what? Why would I be?"

Rei nearly clapped a hand over Nagisa's mouth to silence him, but instead held him back. "What Nagisa means to say is, it's quite scandalous to see you swimming in the nude with another man, but he is glad to see your heart is still in the right place."

"Thanks for the translation, I think," Rin grumbled. The shark was feeling pinned down at the moment, despite the fact that Rei had just very narrowly saved him from that fate. At least Haru hadn't joined in on it, and Makoto and Sousuke seemed to be having something of a moment to themselves, rather than choosing to make Rin feel even more as though he should crawl out to the beach and start digging until he had made a tiny pool for himself, crawling into it, as if that would make him cease to exist.

"Rin can swim any way he wants, as long as he is free," Haru remarked from his spot on the blanket, and even as it sounded silly to everyone else in the room, Rin understood. Haru always knew what to say, instead of poking and prodding with questions, he could skip right over them and get right to exactly what Rin needed to hear. It was an insightfulness that Rin could be grateful for.

Free?

_For me, what would it mean to be free?_  He wondered. _I never really felt trapped on land, but maybe I do need to go home. I'm too scared of hurting Ai again, of doing something horrible. But all I want is Ai to be happy..._  he thought.

Luckily, Nagisa had already skipped over the topic and was rambling on about something else, with Rei interjecting to correct him every minute or so. Makoto suggested that they all play card games to pass the time, but that the rain wouldn't be stopping until morning. Rin didn't ask how he knew. Something about Makoto felt powerful, terrifying, aside from the fact that he was an orca, one of the very few creatures higher than Rin in their social structure.

They played for awhile until Nagisa got caught cheating and Sousuke gave up, dozing on one of the futons. Eventually, Makoto covered him with the blanket and scooted in beside him.

One by one, each of the members of the Iwatobi swim club went to bed, leaving Rin sitting by the window with his thoughts. Haruka got up at one point. He didn't ask any questions, just a towel around Rin's shoulders, telling him to be free with his dreams.

Rin didn't remember falling asleep, but when he did, it was to the sound of rain and waves in the distance. He prayed that his dreams would be serene; in a place that was warm and sunny, where the currents took him to reefs of rainbow and seaweed that danced far from fear or worry or pain.

**Notes for the Chapter:**

> So, this chapter is sort of a one-of-two parter. The next chapter will contain some graphic imagery, and the tags will be updated soon to reflect that, so just an advance warning! My biggest apologies for the slow updates, and thank you so much to everyone who has read this so far! We only have a few chapters to go, but a LOT still has to happen in the story!


	9. Chapter 9

**Notes for the Chapter:**

> Just a quick warning! This chapter does have some violence and a description of the wounds inflicted. If that stuff is too squicky for you, feel free to just skim the dream sequences or skip over them.

Ai couldn't be sure how to explain his feelings towards Momotarou. He was energetic, but not rude like Nagisa. He was intense, but more excitable than his brother. His weird ramblings about nothing in particular and excited attempts at conversation were straddling a delicate line between "endearing" and "obnoxious." Prying Momotarou--or "Momo, for short," as he insisted he call him, rather than "Momotarou-kun," off of his leg was one battle made completely futile by the next clap of thunder, when the other teen would wrap himself around Ai's arm or torso instead.

The struggle went on for several minutes, until Momo admitted he would feel safer in a "fort," so the two of them fashioned a tiny tent out of bedsheets by draping them over the backs of the hotel room's desk chairs. Once huddled underneath it, Momo promptly wrapped himself around Ai's arm at the next clap of thunder.

"Hey, hey, hey, stop! I thought we went over this! We build the blanket fort, no more clinging," Ai exclaimed, prying him off for what felt like the twelfth time. "You said you're a dragon. Dragons shouldn't be afraid of thunder. Especially if you're huge!"

"Well uh, actually. I'm only like this big in my true form," Momo explained, spreading his thumb and forefinger as wide as they could, holding it up so Ai could see. "But just you wait! In two or three hundred years, I'll be bigger than this room! Just you wait, Nitori-senpai!"

Ai didn't have the heart to ask him to stop calling him that. After all, it was a welcome change, being someone else's senpai for once. "Um. Okay. If I promise I'll uh, protect you from the thunder, will you let go of my arm?" Ai was practically begging him now.

"Fiiiiiiine~" Momo whined. "But then we should do something fun! It'll distract me! Wait, I know! How about we play a game?"

"Um?" the elder boy asked.

"I know of one we can play right here in the fort," the redhead began, as if Ai hadn't even made an attempt to speak. "It's a question game, like truth or dare, but just with truth! I ask a question, you answer truthfully, then you get to ask me a question! But if I have to pass, you get to ask another question. Get it?"

Ai got it, but he didn't really understand the point. Still, he figured that he may as well let the younger Mikoshiba enjoy himself for now. "Yeah, I get it," he said with a nod.

"Okay then, I'll go first!" Momotarou began. "What's your favorite color?"

Ai blinked. What kind of question was that, for a truth or dare sort of game? "Uh, I'd have to say purple. Um, have you ever seen a giant squid? Like, do they really exist?"

"Psht, duuuh!" Momotarou answered with a chuckle. "Okay, my turn! What's your favorite kind of beetle?"

"Um? Blue ones? I think?" Ai half-asked, half-answered. "What's the biggest fish--no, uh, sea animal you've ever seen?"

"I would say the squid, but the kraken, duh! Okay, my turn!" Momo scooted forward underneath their makeshift tent, rolling his eyes. "Gosh, you're such a landfish, senpai."

Ai blinked. "Land...fish?"

"Oh! I didn't mean it like, in an insulting way, or anything! I meant that you spend most of your time on land! Anyway, my turn! Do you have a crush on anybody?" Momotarou asked, pointing a finger at Ai in accusation.

"Me? Well, I um," he most certainly did. Anytime he thought of Rin, his heart raced. He thought of Rin kissing him, of Rin holding him close. He thought of Rin like some feral creature of the deep, but also like a piece of heaven he could never reach. _Okay, maybe that's sort of melodramatic._  He thought to himself. "Yeah, I guess you could call it that."

"Oh! Who? Tell me, tell me!"

Ai chuckled. "Hey, you used your question. I get to ask another, first!"

Momo pouted, but seemed to accept it. "Well, um, uhhh... bluh, fine!"

Ai rubbed the back of his head sheepishly. "Ok, my question is..how old are you, really? I got that your brother is really old, but he only looks eighteen. I mean, he's a third year at our school and everything, so, what about you?"

"Aw, senpai! Nah, I'm seventy-five, but the age I choose to present as is fifteen! So you still get to be my senpai!"

Ai fought back the urge to groan. "Well, thanks, I think?" Momo wasn't rude, he was just... overwhelming. He didn't know how to handle anyone being that excited about _him._  He was kind of cute, though. _Cute like endearing, not cute like Rin. Rin's a subtle sort of cute that shines through when he smiles or gets ready to dive into the pool. Cute in the way he screws up his face when he thinks too hard about something, or cute in the way where he looks so peaceful but also kind of silly when he leaves his mouth hanging open in his sleep._

"Anyway, my turn again! Now I get to ask! Who do you have a crush on?"

\--

That night, Ai's dreams were restless. He imagined he was underwater, not too far from the surface, either. He could see the sun playing across the water's surface overhead, but he was rooted to the rocks below. He couldn't walk or swim, only crawl across the bottom, gripping the brightly-colored coral beneath his fingers tightly, and it broke off in his hands. As he crawled, fish and brightly-colored imaginary mermaids stared, then ducked away anytime he looked in their direction, hiding behind seaweed, rocks, coral, and anemones.

Ahead of him was a white-tipped tailfin, the kind he had seen behind Rin at the aquarium. The water around it glowed a dull red as it swam away from him, always the same distance away, no matter how fast he crawled. To Nitori, it _was_  Rin.

Rin was always ahead of him, swimming away, forcing his way through the reef, away from him. He crawled out to Rin time and time again, but his voice was gone, and all that escaped his mouth were bubbles. Sometimes he would think he was close enough to reach out to Rin, who had the head and arms of a human, but the body of a shark, and the shark would turn to him, eyes filled with fear, and bat Nitori's hand away before swimming away again. Try as he could, Ai couldn't pull himself off of the bottom, so the final time he managed to get close to the shark, he jumped on him, closing his arms around him in a desperate movement.

The shark cried out in pain and bit Ai's hand, kicking away from him. Ai jumped and pulled back, sobbing through the water. He murmured "Why, why, why," over and over again as the bubbles escaped his mouth, but Rin just stared at him, eyes wide with fear. 

"Because I'm not like you," the dream-Rin hissed, and Ai looked down at his bleeding hand. It was covered in long purple spines. His arms were covered in spines, and he gazed at them in fear, trying to rip the appendages from his body. "No, no! Wait, Rin!" he begged, stumbling after him again. "Rin! I don't care! I don't care if I'm awful for you! I love you!" he begged, surprised at his own words. He never said anything like that to anyone in his life.

Dream-Rin just glared at him, and he stared down at his hand. The blood from it formed a red cloud,  bursting forth and obscuring his vision. He tried to brush it away, to clear the water, but all of it was red, and he could hear Rin's whisper repeating, his voice beside his ear loud enough that it echoed throughout his mind.

_"Not like you."_

_Not like you. Not like you._

_Notlikeyou, notlikeyounotlikeyounotlikeyou HE'S NOT LIKE YOU!_

Ai sat bolt upright in his bed, sweat trailing down his face. He was panting, and the room was dark. On the other bed, Momotarou was stretched out: his hands underneath one pillow, the other on the floor, his mouth wide open as he slept soundly.

The digital clock on the nightstand declared the time with an eerie blue glow: 3:25 AM.

Ai fell back onto the pillow, trying to keep his breath under control. His hands were clammy and his face was hot, but he still flipped the pillow over, burying his face in it.

He didn't go back to sleep that night.

\--

Rin lay back on the blanket, staring at the ceiling. Haru lay beside him with his back to him, and Rin could feel him breathing lightly. The rise and fall of his chest kept a comforting rhythm, and Rin only wished he could feel that serene himself. No doubt Haru was dreaming of some far-off ocean, swimming through imaginary waves with imaginary fish. Or perhaps they were real, and this was his dream reality. The shark could never explain it, but Haru was the sort of person Rin felt a tight familial kinship with; the origins of which he could never quite understand.

He wished he could will himself to be that calm and dream perhaps of swimming as well. He closed his eyes, trying to remember the sound of the waves as they were heard from below, and bubbles as they passed by his head. He forced himself not to move, laying there with his eyes closed until he finally drifted off.

The depths above and below were endless, so he believed he was out in open water, but from somewhere he could see a soft ambient light lighting his way, penetrating the water before him. Above him was a shadow, the silhouette of a small form, and he swam up to investigate, circling from afar at first, then approaching carefully.

It was Ai. His eyes were half-lidded and his body was still, but somehow Rin could tell he was still alive. He fell through the water slowly, his arms and legs limp, not even bothering to fight, to try and swim back to the surface above.

Rin's first instinct was to panic. How far above was the surface? Could he make it back to the open air before Ai's air ran out?

_Did it even matter?_

He nudged Ai's body with his head. No response. Ai turned his head to look at him in a slow, isolated movement, but his face betrayed no emotion. He looked empty. Rin touched Ai's cheek with a clawed hand, outlining his face. He held his head in his hands, pressing their foreheads together, nudging him again gently. After a moment that felt like a lifetime, he lifted his head, sinking into an upright position, wrapping his arms around the boy's torso. He looked so pathetic. So vulnerable. And he smelled like... blood.

From seemingly nowhere, blood clouded the water as it had in the Samezuka school pool. It filled the water around them, blossoming into clouds, filling Rin's nose and mouth. He clawed at the water, trying to dispel it, but it remained, forming ribbons that led back from Rin's claws and mouth...to Ai. Rin very nearly released his grip on him in horror. It was coming from where Rin had touched him. His face, his arms, even his torso. The smell and taste was overpowering; he felt the bombardment of his senses might throw him into a frenzy.

_How much could one bite hurt?_

_No! I'm not a man-eater!_

_He's so delicate._

_But he's so tantalizing._

_No one will ever know._

_What could it hurt?_

_Jut a tiny nibble, a love bite, really._

_I promised myself I would never hurt him!_

_No!_

He pulled Ai's body close, nuzzling into his neck. No, he'd never hurt him. He wasn't going to make him suffer. Not now, not ever. He kissed his cheek, trailing his fingers down his chest. No, Ai was precious. He was delicate, happy, a gentle creature from the land...

He closed his eyes, his cheeks pressed against Ai's as they sank together through the water, and Rin realized he was crying. He let himself sob, clinging to Ai, only to open his eyes and find his claws buried in Ai's skin, his skin bitten and torn away, cleaved clean from the bone. He released him, watching the mangled body float down, away from him.

Rin awoke in a cold sweat. Outside, the sun would have been just barely staining the horizon orange, if it hadn't been obscured by the remains of dark clouds. Birds were beginning to chirp somewhere in the distance. Haruka stirred beside him, and he opened his eyes to look at Rin. He said nothing, letting Rin catch his breath, and lay back down, pulling a portion of the blanket close to him. They lay there together in silence, and Rin swallowed thickly. He liked that about Haru: he didn't need words to understand anyone or to take in a situation. He sat, silent, understanding, wordlessly caring. Makoto was all words and questions, trying to talk through problems and sticky situations, a tactic which Rin sometimes likened to a busybody. Rin was grateful that just wasn't Haru's style.

Rin did have to use words though, and he knew Haru would choose any he used carefully, that they would mean exactly what he meant.

"Haru?" he whispered.

The raven-haired boy looked at him.

"What do you do if you're afraid of hurting someone?"

"Do you want to hurt them?"

"No, but..." Rin began, gnawing on his lip.

"Then don't," came Haru's flat reply.

Rin fell silent once more for a few seconds. "But what if I do?"

"Why?"

"Why what?"

"Why would you?"

Rin hesitated. Well, there were a million reasons he had convinced himself earlier, but suddenly they all left him. He couldn't think of any. The only thing he was afraid of now was himself. His own inability to deal with blood--the sight of it, the smell of it everything about it left Rin reeling, struggling for a grip on his instincts and reality. "Because I can't control myself."

"But you don't want to." Haru affirmed.

"No, of course not!"

"Then don't. You won't if you don't."

Rin nodded slowly, even if he didn't fully understand. _Was it really that simple? Could it be that simple?_  He wasn't sure if he could contain himself just because _he wanted to._

Haru nodded. He gave Rin his usual I-trust-you-don't-be-stupid nod, then rolled over and dozed off for two more hours, leaving Rin alone with his thoughts.

\--

Within a few hours, the rain had slowed to a sad drizzle, leaving everything soaked, and puddles in any crevice nature would allow on the island. Makoto walked Rin and Sousuke back to their hotel, carrying that same aggravatingly genuine soft smile the entire walk. He bid the both of them farewell, regarding Sousuke slightly more than Rin, and Rin couldn't help but feel as though the two of them were conspiring against him somehow. Sousuke always seemed like he was up to something, and chatting with Makoto all of a sudden; if dealing with one sea guardian was annoying enough, two-- two who also happened to have some sort of unclear definitely-not-boyfriends-maybe-heterosexual-life-partners relationship-- were sure to be up to no good.

They had a few hours off that day, since Mikoshiba believed that rest was just as important as a hard day of work, a fact for which Rin was grateful.

He tried to take Haruka's advice to heart. Whenever he thought about Nitori, he always found himself listing the reasons he couldn't have him to himself over and over like a mantra. It was if he was trying to convince himself that his kouhai was completely off-limits. Actually, that was exactly what he was doing. Ai had flat out _told him_  that he liked him, so Rin felt even worse about making all of these excuses to himself to blow him off.

_He's not like me._

_I'm dangerous._

_What if I hurt him?_

_He has no idea who I really am._

_He's just a human._

_Humans are off limits._

_In his eyes, I'd be a monster. He'd be terrified of me._

His mind bombarded him with reasons, and his heart ached. His heart and his mind were at odds.

Now Rin had to step up. He had to _do something_ , instead of just brooding about it.

\--

Standing ouside the door to Ai’s hotel room, Rin didn't feel quite so confident. Sure, Ai said he liked him, but. Words. Words were a struggle.

He knocked.

A bleary-eyed Ai answered the door in a wrinkled Samezuka tee and workout pants.

"Senpai? What's... up?" He asked through a yawn.

"Would you... would you want to come swimming with me before practice? Not laps, I mean in the ocean. It'd be just the two of us."

Nitori perked up, bouncing on the balls of his feet. "Would I ever!" he exclaimed, then stopped, dropping down to a whisper. "I mean--would I ever. Just let me change real quick. I have to be quiet or I'll wake up my room buddy," he explained meekly, his shoulders slouching a little before ducking away from the door to grab his jammers, pulling them on beneath his pants.

The sand on the beach was damp and compacted from the storm the previous night, arranged into small "waves" of sand from where the waves of high tide had repeatedly buffeted against the shore the previous night. Ai and Rin left their shoes in the grass and walked along the water's edge together, letting the waves rush up to meet their ankles, turning each of their footprints into tiny pools trailing in their wake.

Ai was the first to speak. "Rin-senpai! Is it okay if I ask you a personal question?"

The shark shrugged. "Fine, what is it?"

"Okay, um. Senpai, please don't take this the wrong way, but. Am I bad for you?"

Rin had no idea how he was supposed to take that. Bad for him? Ai was wonderful, the object of all his desires. Ai was everything he wanted, yet he felt untouchable. _No, Rin. The only thing stopping you from being with him is you!_  He forced out a chuckle, but it sounded as dry and fake as it felt. "Bad for me? What the hell do you mean?" He turned to Ai, slinging an arm around the smaller boy's shoulder. "You're not bad for anyone, okay? You're great. I just... have issues."

Ai rolled his eyes, ducking out from under Rin's arm, but taking his hand. "Senpai, I like you a lot, but..." he wasn't sure what to say. He cut himself off, staring off into the ocean.

"But nothing!" Rin retorted, pulling him in close suddenly. "Aiichirou, I..." he released Ai's hand, reaching up to cup his cheeks in his hands. Ai's eyes widened, and Rin found himself lost in his gaze. He was so innocent, so beautiful. He wanted to protect him, to hold him forever, but doubt and uncertainty grabbed him by the stomach, threatening to tear him in half. He wanted to cry out in frustration, and kiss Ai, bite Ai, take him right then and there in the sand.

Ai's lips were barely parted, suspended in a look of surprise. Rin wanted him. He was sick of being afraid. He leaned down, planting a soft, chaste kiss on Ai's lips. "I don't just like you, I love you."

Ai stared at him, half in shock, half in wonder, as if he were trying to reassure himself that yes, what just happened was indeed real. He reached up, snaking his arms around Rin's neck, and pulled him in so close that their chests were nearly touching, their foreheads pressed against one another. They stood there for what felt like an eternity to Rin, before Ai drew him into a slow, careful kiss. He pressed his lips to Rin's, parting them slightly to allow Rin to move in, taking Rin's lip in his own.

Oh, how Rin wished he had done this a week sooner. Standing in the aquarium, sitting on the bus, waiting at the bus stop, anywhere. He could have been kissing him. He could have been kissing him time and time again, and he wished he could rewind time and just kiss him that first time they had gotten lost in the rain. He deepened the kiss, letting his tongue glaze across Ai's lips, and Ai pulled it into his mouth with vigor, sending a charge down his spine. He let his hands slide down Ai's cheeks and back to wrap around his neck from behind, one hand cradling his head, holding his chin up delicately.

Time seemed to stop around him, and he pulled their bodies flush against one another. Having Ai in his arms was a feeling he couldn't possibly describe. He could never hold him tight enough, kiss him passionately enough, or pull him close enough that he could find a way to express his happiness to have Aiichirou in his arms. He wanted to burst out of his skin and scream into the sky in sheer excitement.

When their lips finally parted, he inhaled sharply, pressing his forehead against Ai's drawing in every last trace of his scent. He couldn't describe what he smelled like anymore, Ai was just Ai, and he wondered if the smell of the ocean around him was overpowering his senses at that moment. After all, everything about him, every last piece of him was beautiful and perfect to Rin.

"You have no idea how long I've been waiting for you to say something like that to me, Senpai. I love you too."

Ai was smiling. He seemed to radiate happiness and something else that Rin found comforting, perhaps it was hope. He pulled Ai flush against him again, checking for himself this time that this was reality and not another dream.

"Come on, let's go swimming."

He and Ai dragged each other into the shallows, but they didn't do much swim training. They left their wet shirts and jackets in the sand, and the waves knocked against them when they were thigh-deep in the water. Ai kept pouncing on Rin's back, trying to drag him under whenever he thought the shark would least expect it, and Rin would splash him and grab him around the waist anytime he tried to swim away,  chuckling as he dragged him under. That is, until Ai tickled him and he released him. Then the process would repeat again, sometimes the other way around.

After a while, they laid in the water together, holding hands as the waves rushed over them. Rin watched the clouds fly by overhead, and listened to Ai's laughter when a wave washed over them both, very nearly going up his nose. He sank in an upright position, letting Ai grab him around the waist. They floated there together in silence, Ai resting his head on Rin's shoulder, looking up at him. Rin watched him, his arms looped around Ai's torso. He wanted to kiss him again, but he also wanted to grab him and bite into him--not viciously, but lovingly. He would smother him in kisses and nips, carefully, only breaking the skin when he dared to, leaving his marks. He'd gently lick the wounds, ensuring that none of them would bleed too horribly.

"You can bite me, if you want."

_Fuck, was I staring at him THAT intently?_

Rin froze, his voice leaving him suddenly. "Wh-what?" he stammered.

"I said you can bite me. I know you want to, the way you looked at me. I mean! Um! If that's what you wanted! You've been staring at me for awhile now, but I know you won't hurt me," Ai whispered.

"Ai! Do you even know what you're asking?!" Rin scolded, tempted to shove him away.

"I could tell you wanted to," Ai admitted, blushing.

"Whether I want to or not doesn't matter," Rin answered, looking offended.

"I don't know, I'm saying I'm okay with your kink."

"K-KINK!? It's not a kink! It has a. A um! A deeper intrinsic meaning than that to me! I don't really know if I can tell you about it." He let his hand stray up to cradle Ai at his neck, his fingers running through the short hair on the back of his head. Ai had what felt like the silliest teasing look plastered across his face.

"Well, if it means a lot to you, this is me giving you permission," Ai said, his voice dropping to a whisper. "I'm telling you that it's okay, I don't want you to force it, but I do want you to feel free to do whatever you want with me."

Rin opened his mouth to protest, and it hung there for a few seconds before he finally shut it. How could he tell Ai that _it wasn't like that?_  Biting was a _ritual of claiming another as yours and yours alone? A deep, consensual bond made between mates, especially those of different ranking?_  He fought back the urge to sigh.

He did feel free with Ai.

If all the ocean was a cage, did he really feel free anywhere else? It felt almost alien, being here. He was in the ocean, but Ai was there, by his side. Sure, they were standing here in the shallows, waves pressing against their chests, but it was still the sea, and they still stood on the very edge of land. It felt odd to be here, but at the same time, Rin found it to be both fitting and reassuring. He kissed Ai gently on the lips, basking in the radiance of Ai's smile for as long as he possibly could. "I _do_  feel free with you. I doubt you could understand, but no one, no, _nothing_ , could possibly make me feel as free as you."

He pressed his cheek to Ai's, feeling his warmth and the damp wetness of his skin. He was so wonderful to take in, so perfect to be with. Even now, he smelled like the ocean. Did he always smell like that? His shoulders were sculpted and sturdy, with all of the power of a seasoned swimmer. Had he always been that strong? Was it something Rin hadn't noticed? He wanted him.

He wanted to hold him close, you he wanted to take him and keep him. He could, Ai gave him permission, but would it be wrong? Would he be disgusting for taking him?

_Did he even care at this point?_

He held Ai close, kissing his cheek and all along his jawline. He traced it with his fingertips, kissing and nipping at his earlobe until he reached down to the edge of his neck, kissing him again. Ai's arm reached up to stroke Rin's cheek as he kissed his neck over and over, along Ai's left collarbone and up to his ear. He teased the skin, until finally opening his mouth, sinking his teeth into the skin at the base of Ai's neck. He was cautious, precise. He thought of it like biting into a fish that had spines or scales. Bite down in he right place, with lightning-quick motion and instant, yet delicate precision. He broke the skin, but did not shut his jaw. Blood beaded out, dripping from the wounds and into his mouth but he refused to let himself go any further. He would not dare to tear any flesh from the bone. Instead, he withdrew slowly, and licked any extra beads of blood that surfaced on Ai's skin. It wasn't sweet. It was metallic, it was salty, but Rin found it perfect. Just letting a drop of it hit his tongue set an electric charge down his spine.

Ai winced from the pain, his arms, looped around Rin's neck, tightening, but he didn't cry out. He leaned into Rin, a small "ah" of surprise escaping his lips when the shark bit down. It hurt, but the pain didn't feel entirely bad. He felt that he and Rin were sharing something much deeper than a kiss, in a way. He knew he could endure it for Rin. When Rin pulled away to lick the wound, Ai gasped audibly. "That's not gross to you?"

Rin's eyes were half-lidded, but he stopped, reaching up with a hand to wipe the blood off of his lips. "It should be, shouldn't it," Rin answered, looking grim. Ai softened at the guilty expression on his face,

"Well, kind of, but I wouldn't worry about it too much! I said it's okay for you to bite me, didn't I?"

Rin was surprised to feel a blush creeping up his cheeks. "Yeah," he murmured. "I uh--ow!" He groaned, cupping his mouth in his hand.

Ai straightened, reaching for Rin's hand on pure reflex. "Are you okay? Did I do something?"

"No, not at all," Rin mumbled, spitting a small mixture of blood and saliva into his hand. He whined through his nose, then spit again, and Ai was horrified to see a bloody tooth in his hand.

"Oh! Ohmygod _Rin!_  Are you okay? Should I get something? You should come back to shore and I'll let you bleed into my tee shirt until we can get you to a doctor or something! Maybe I could call captain Mikoshiba and we could get an ambulance, but we're not on the mainland I--" He was cut off by Rin grabbing his arm with his free hand.

"Stop. I know it's gross but I uh... I have a condition? I don't have a way I could explain it where it would make sense to you. But uh, I lose teeth all the time. Don't worry about it." He knew a new one would replace it within a few hours--shark teeth grew on a rotation since they broke off so easily so they could replace themselves. However, it was hard to explain something like that to Ai. Human teeth were far less expendable, and far less easily replaced. He hoped Ai wouldn't ask too many questions he didn't have the answers to, because to a degree, he felt downright silly.

Ai looked at Rin, then back down at the bloody tooth in his hand. He seemed disgusted, but Rin felt relief wash over him when he elected not to ask any more questions. "Um. Senpai. I have a weird, request, then."

Rin couldn't resist the urge to nudge Ai affectionately with his head. The younger boy shot him a look of confusion, but a smile tugged at the corners of his mouth, and Rin let out a silent breath of relief. "What is it?"

"Can I...keep it? The tooth, I mean," he blushed, looking away in embarrassment. "If not, it's okay!"

"Er, no, it's fine," Rin whispered, kissing him on the cheek. "you can have it, if you want. Just don't use it for a voodoo ritual against me or anything. I give you my gross tooth in hopes that you don't do other gross things with it." He rinsed it off in the saltwater and handed it to Ai, who waded back towards the beach until he could safely toss it on top of his jacket.

"Thank you, senpai," Ai murmured, very nearly jumping into Rin's arms when they were only knee-deep in the shallows. "Are you sure you're going to be okay, even after you just lost a tooth?"

Rin sighed. _What am I supposed to say? How the hell do I reassure him without telling him anything?_  he wondered to himself. "Nah, look, I'm fine. See?" He bared his teeth, revealing them to him. There was hardly any evidence that he had lost a tooth, other than the gap where it had once been, and his saliva had already washed most of the blood away.

"Oh. Um. Well okay. I'm glad you're all right," Ai replied, pulling him close and nuzzling his face into Rin's shoulder. "Is it...is it okay if I kiss you again, then?"

Rin nodded, and Ai pulled him into another exuberant kiss, smiling into Rin's lips. Ai made a small squeak of surprise when Rin hooked an arm behind Ai's knees, scooping him up so he could hold him at a level where they could see eye to eye. Rin couldn't help but laugh at the noise, and Ai frowned mockingly into the kiss, nipping at Rin's lip. He let his arms rest against the back of Rin's neck, letting a finger twirl in a bit of Rin's wet hair. He pulled his legs up, hooking them around Rin's waist and holding himself up. He broke one of his hands away to trail his fingers down Rin's chest, outlining every last contour, every trace of muscle beneath the skin. The saltwater stung the open wounds on his neck, but he ignored the sting, focusing only on Rin.

"I love you, Senpai," he breathed, breaking the kiss to rest his head against Rin's shoulder.

Rin let the hand under Ai's ass grope him, just a tiny feel. He was, by no means, a connoisseur of human behinds. He only had one himself in his human form, but Ai's was small, firm, and muscular, and it fit just perfectly into the arch of his hand. If it was socially acceptable to have a favorite butt, Ai's was his. However, that could also just be the desire talking. After all, he was already sickeningly aroused by the taste of Ai's blood and the smell combined with their sweat and the saltwater. He knew Ai could feel it. He could probably see it in his eyes, and more obviously, feel it as his growing erection pressed against Ai's inner thigh. He could never get enough of him. His scent, his muscles, the way he was blushing with his lips slightly parted, looking at Rin with complete trust made Rin feel crazy. On the bright side, he knew Ai was aroused as well, as he shifted himself against Rin's waist, and Rin fought back the urge to groan in frustration from the warmth already pooling in his stomach that was bringing his cock to attention.

He was impressed with Ai's litheness, however, as the smaller boy was beginning to tent his jammers as well, and had slid himself closer to Rin, their chests nearly touching, their spandex-clothed erections just barely grazing one another.

Ai let out a small pant, and Rin lifted him, practically stumbling up onto the beach to lay Ai back in the sand, which seemed softer than the pebble-ridden waves of the shallows. Too bad sex on the beach sounded gross. Well, human sex, at least. He never had to worry about lubrication for himself, but human sex was nowhere near as simple. The very thought of sand and silt salty in such undesirable places made him blanch. He kissed Ai, sloppily, wetly, but it was full of pure desire and want, and Ai returned the kiss with fervor. He slid his knee between Ai's legs in the sand, and the smaller boy rolled his hips up to meet his, sending sparks up the shark's spine.

They didn't even need to take their swimsuits off as they reached for each other, all hot kisses and groping and Rin's _sure_  he's leaving bruises on Ai's hips he never intended to leave with how hard he's gripping him. He feels guilty for it, but not very, he's too engulfed in the haze of pleasure when he's bucking against Ai again, quickly, messily, without rhythm as much as there is need, they're just rutting against each other through the spandex. Ai presses his face into Rin's shoulder, mewling softly, and Rin feels like his whole body has been electrified.

Rin lets out small moans and pants, kissing and nuzzling Ai's neck before biting into him again, careful not to draw blood this time, though he's lost in Ai's desire just as much as his own as he wrestles for more friction. Luckily, Ai is flexible, and loops his legs up around Rin's hips. The shark's surprised to see him in such a vulnerable state, his eyes half-lidded, his cheeks flushed, a mewl becoming a soft whisper of "Senpai, please."

He wants this moment to last forever and Ai's squirming beneath him has Rin so filled with need that he's letting a hand stray down Ai's abdomen, reaching down into his shorts, dexterous fingers wrapping around Ai's cock. The silver-haired boy moans out another wavering "s-senpai," amidst his moans and digs his nails into Rin's back, unknowingly raking scrapes into Rin's skin and Rin feels it like a jolt. He's lost his rhythm completely and Ai seems to notice, because suddenly his palm is against Rin's crotch and he's too hot and too close and he feels like he might explode. He shudders when everything goes white and he _knows_  he's just come inside his swimsuit, but he doesn't care, as Ai's teetering on the edge, and Rin's shivers send him over it, rutting helplessly against him for _more_ , until he comes all over the inside of his shorts and Rin's hand, and something inside Rin is so satisfied, feeling so disgustingly _dominant_  and _proud._

_Yes, Ai was his._

\--

Ai was grateful to find the hotel room empty when he returned, and he took the opportunity to stare at the bite marks that now graced his neck in the bathroom. The area around it was sore and bruised, which made him sigh. There was no hiding this. He'd have to come up with some ridiculous excuse for the team, but he had a feeling captain Mikoshiba would be able to see right through it. Massaging it did little to help, but he reminded himself of all the soft, gentle kisses Rin had pressed to his neck, in spite of the still-open wounds.

Just how deeply had Rin bitten him? Terrified of infection, he took a long, hot shower, carefully rinsing his neck off. He didn't want to scrub the wounds directly, so he lathered up some soap on a washcloth, letting it lay over his neck while he ran water over it and washed the sand out of his hair. He laid a hand against the washcloth, remembering each of Rin's kisses with fondness. Around the wounds, dark, reddish-purple marks were forming, not quite bruises, but actual colored markings gracing his skin.

When he emerged from the shower, he inspected them in the mirror, letting his fingers pass over the skin. Did this mean he belonged to Rin? He knew they had some sort of meaning in fish society, but he wasn't sure if he should ask what. Momo would know he was just an ignorant human and not just a "landfish," as the dragon had called him earlier if he dared to ask. He wrapped his neck and the edge of his shoulder in gauze, deciding that maybe he'd ask Sousuke. Maybe later.

Ai spent the last day of their trip training, and he fell asleep almost as soon as he hit the mattress that night; in spite of the excited ramblings of Momotarou by his side. Momo was congratulating him for something, but he drowned him out with his own thoughts, too busy thinking about Rin to listen properly. He woke up just long enough to spend a bit of time doing some homework, then napped until Momo shook him awake for breakfast.

On the ferry back, Ai sat to the outside, listening to the sound of the waves. He didn't see Rin on the boat, but on the bus he scooted in beside him before Sousuke could. He was grateful that Sousuke didn't protest, and instead let his head rest against Rin's shoulder, his hand resting on Rin's thigh. Rin noticed, sliding his fingers underneath Ai's, intertwining them. They sat like that for some time, and Rin pulled their hands up to his cheek, kissing the back of Ai's palm just when he thought his kouhai wasn't paying attention anymore. Ai smiled, nuzzling into Rin's shoulder.

At that moment, everything was just right.

  
He didn't want anything else in the world.   


**Notes for the Chapter:**

> I can't believe how long it's been since I last updated this fic, wow I'm so sorry. I'd had this chapter written for actual ages, but it took so long to get around to editing. I have the last two chapters planned out, but yeah, I hope you enjoyed this, thanks for sticking with me through this story!
> 
> So the biting thing actually does have root in something, sharks bite each others' necks when mating, it's really common. In this story, bite marks indicate that a fish is "taken," regardless of their social status, but especially if they're a lower type of fish on the food chain, it shows that they're protected and that it's probably bad news to mess with them, because messing with that fish means messing with their mate. Yeah.


End file.
